Tüm alıştırma soruları

2789 soru

Soru 2701Soru

Which word completes the text with the most logical and precise meaning?

Aşağıdaki boşlukları doldurun

For decades, planetary scientists assumed that the surface of the dwarf planet Ceres was completely dry and geologically inert. However, recent data from the Dawn spacecraft revealed localized deposits of bright sodium carbonate, suggesting that briny water from a subsurface reservoir had erupted onto the surface. This discovery has forced researchers to revise their initial models of the dwarf planet's history, indicating that Ceres's geological activity is far more than previously believed.
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Cevap

dynamic
The correct word must describe Ceres's geological activity as ongoing or changing, directly contrasting with the previous belief that the dwarf planet was 'geologically inert.' Words like 'dynamic' or 'active' logically and precisely fit this context.

Adım Adım Çözüm

1
Analyze the context clues in the passage.
The passage contrasts the traditional view of Ceres as 'geologically inert' (inactive) with new evidence showing eruptions from a subsurface reservoir.
Identifying semantic contrast helps determine the required meaning for the blank.
2
Identify a high-utility academic word that completes the contrast.
The word must mean the opposite of 'inert' to describe active geological processes, such as 'dynamic' or 'active'.
This completes the logical transition from assuming the planet is inert to recognizing its ongoing activity.

Anahtar Kavram

Using context clues to determine the precise meaning of high-utility academic words.
Tahmini Süre:1m 0s
Soru 2702Soru

In triangle PQRPQR, a line segment parallel to QRQR intersects sides PQPQ and PRPR at SS and TT, respectively. If the length of segment PSPS is 2x12x - 1, the length of segment SQSQ is 33, the length of segment PTPT is x+2x + 2, and the length of segment TRTR is 22, what is the length of segment PSPS?

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Cevap: 15

Cevap

The length of segment PSPS is 15.
According to the Triangle Proportionality Theorem, if a line is parallel to one side of a triangle and intersects the other two sides, then it divides the two sides proportionally. Therefore, we can write the proportion as PSSQ=PTTR\frac{PS}{SQ} = \frac{PT}{TR}. Substituting the given values yields 2x13=x+22\frac{2x - 1}{3} = \frac{x + 2}{2}. Cross-multiplying gives 2(2x1)=3(x+2)2(2x - 1) = 3(x + 2), which simplifies to 4x2=3x+64x - 2 = 3x + 6. Subtracting 3x3x and adding 22 to both sides results in x=8x = 8. Substituting x=8x = 8 back into the expression for PSPS gives 2(8)1=152(8) - 1 = 15. Thus, the length of segment PSPS is 15.

Adım Adım Çözüm

1
Set up a proportion using the Triangle Proportionality Theorem.
PSSQ=PTTR\frac{PS}{SQ} = \frac{PT}{TR}
Since segment STST is parallel to side QRQR, it divides the sides of triangle PQRPQR proportionally.
2
Substitute the given algebraic expressions into the proportion.
2x13=x+22\frac{2x - 1}{3} = \frac{x + 2}{2}
This establishes a solvable equation for xx based on the geometric relationship.
3
Cross-multiply and solve for xx.
2(2x1)=3(x+2)    4x2=3x+6    x=82(2x - 1) = 3(x + 2) \implies 4x - 2 = 3x + 6 \implies x = 8
Cross-multiplication removes the denominators, allowing us to isolate the variable xx.
4
Calculate the length of segment PSPS using the value of xx.
PS=2(8)1=15PS = 2(8) - 1 = 15
The question asks for the length of segment PSPS, so we must evaluate the expression 2x12x - 1 at x=8x = 8.

Anahtar Kavram

Triangle Proportionality Theorem and Similarity
Soru 2703Soru

To create a specific type of mortar, a builder mixes cement and sand in a ratio of 22 to 55 by weight. To create a concrete mixture, the builder mixes this mortar with gravel in a ratio of 77 to 33 by weight. If the builder prepares 300300 kilograms of the concrete mixture, how many kilograms of sand are needed?

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Cevap: 150

Cevap

150
To find the weight of the sand needed, first determine the weight of the mortar in the concrete mixture. The ratio of mortar to gravel is 77 to 33, meaning mortar represents 710\frac{7}{10} of the total 300300-kilogram concrete mixture. The weight of the mortar is 710×300=210\frac{7}{10} \times 300 = 210 kilograms. Next, since mortar consists of cement and sand in a ratio of 22 to 55, the sand represents 57\frac{5}{7} of the mortar's weight. Calculating 57\frac{5}{7} of 210210 kilograms yields 150150 kilograms. Therefore, the weight of the sand needed is 150150 kilograms.

Adım Adım Çözüm

1
Find the total weight of the mortar in the concrete mixture.
210210 kilograms
The concrete mixture has a ratio of mortar to gravel of 77 to 33 by weight. This means mortar makes up 77+3=710\frac{7}{7+3} = \frac{7}{10} of the total concrete weight. Multiplying this fraction by the total weight of 300300 kilograms gives 710×300=210\frac{7}{10} \times 300 = 210 kilograms of mortar.
2
Find the weight of the sand within the mortar.
150150 kilograms
The mortar is composed of cement and sand in a ratio of 22 to 55 by weight. Thus, sand makes up 52+5=57\frac{5}{2+5} = \frac{5}{7} of the mortar's weight. Multiplying this fraction by the mortar's weight of 210210 kilograms yields 57×210=150\frac{5}{7} \times 210 = 150 kilograms of sand.

Anahtar Kavram

Solving multi-step ratio problems by determining part-to-whole relationships and compounding ratios.
Soru 2704Soru

Many marine organisms contribute to the ocean's carbon cycle, but few have as complex an influence as coccolithophores. These single-celled algae construct intricate calcium carbonate shells, a process that absorbs dissolved carbon from surrounding waters. Under standard assumptions, this shell formation should act as a net carbon sink, helping to mitigate atmospheric carbon dioxide levels. However, the biochemical reaction that produces calcium carbonate also releases dissolved carbon dioxide back into the water column. Consequently, coccolithophores can actually function as net carbon sources under certain ecological conditions, complicating models that predict how marine ecosystems respond to global climate shifts.

Which choice best describes the function of the underlined sentence in the text as a whole?

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Cevap: It outlines a widely accepted assumption about coccolithophores' ecological role that the subsequent sentences go on to qualify.

Cevap

The correct answer outlines a widely accepted assumption about coccolithophores' ecological role that the subsequent sentences go on to qualify.
The correct answer outlines how the underlined sentence establishes the expectation that coccolithophore shell formation is a carbon sink, which is subsequently qualified by the explanation that the process also releases carbon dioxide.

Adım Adım Çözüm

1
Analyze the underlined sentence to identify its primary function and claim.
The underlined sentence states that under standard assumptions, shell formation should act as a carbon sink, which represents a widely expected ecological outcome.
This establishes the initial premise or expectation before the passage introduces new variables.
2
Examine the sentences following the underlined portion to determine how they relate to it.
The transition word 'However' starts the next sentence, which reveals that shell formation also releases carbon dioxide, meaning that the algae can actually act as a carbon source under certain conditions.
This shows that the subsequent sentences introduce a complicating factor that qualifies the initial expectation.
3
Match this relationship to the correct option.
The correct option describes the underlined sentence as outlining a widely accepted assumption that the rest of the text goes on to qualify.
This accurately reflects the part-to-whole rhetorical relationship between the underlined sentence and the overall passage.

Anahtar Kavram

Analyzing the rhetorical function of a specific sentence within a passage, specifically how a statement of standard expectations is qualified by subsequent details.
Tahmini Süre:1m 30s
Soru 2705Soru

In agricultural chemistry, researchers analyze how soil moisture affects the decomposition of synthetic urea fertilizers, which release ammonia gas (NH3NH_3). In a controlled experiment, chemist Dr. Hiroshi Sato observed that in dry soils with less than 10%10\% moisture content, urea decomposition was extremely slow, resulting in minimal NH3NH_3 emissions. However, when soil moisture was increased to 30%30\%, NH3NH_3 emissions rose sharply. Interestingly, in soils saturated with water (100%100\% moisture content), NH3NH_3 emissions fell back to near-zero levels, even though the urea had completely decomposed. Sato noted that water-saturated soils trap dissolved ammonia as ammonium ions (NH4+NH_4^+) in solution, preventing it from escaping as gas. Which choice most logically completes the text?

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Cevap: high soil moisture levels can promote the breakdown of urea while preventing the resulting ammonia from being released into the air.

Cevap

The correct answer is the option stating that high soil moisture levels can promote the breakdown of urea while preventing the resulting ammonia from being released into the air.
The correct option logically completes the text because it directly synthesizes the facts presented. The text states that in water-saturated soil (high moisture), the urea decomposes completely, yet the resulting ammonia is trapped in solution as ammonium ions, which prevents the gas from escaping into the atmosphere. Therefore, high soil moisture can facilitate decomposition while restricting the emission of the resulting gas.

Adım Adım Çözüm

1
Analyze the premises regarding soil moisture levels under 10%10\% and at 30%30\%.
Under 10%10\% moisture, urea decomposition is extremely slow, leading to minimal ammonia gas (NH3NH_3) emissions. At 30%30\% moisture, emissions rise sharply.
To establish the initial relationship between low-to-moderate moisture and fertilizer decomposition/emission.
2
Analyze the premises regarding water-saturated soils (100%100\% moisture).
In saturated soils, the urea is completely decomposed, but emissions of NH3NH_3 are near-zero because the ammonia is trapped as ammonium ions (NH4+NH_4^+) in the solution.
To understand the behavior of the system under high moisture and identify why the expected emissions did not occur despite complete decomposition.
3
Synthesize these findings to identify the most logical conclusion.
High soil moisture (saturation) allows the urea to decompose completely, but prevents the resulting ammonia gas from escaping into the atmosphere.
To select the conclusion that directly follows from the premises without introducing external assumptions.

Anahtar Kavram

Logical Inferences
Soru 2706Soru

A circular tabletop is designed to have a square glass inlay. The square glass inlay is inscribed in the circle and has an area of 6464 square inches. What is the area, in square inches, of the circular tabletop?

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Cevap: 32π32\pi

Cevap

The area of the circular tabletop is 32π32\pi square inches.
The correct answer is 32π32\pi because the inscribed square has a side length of 88 inches. The diagonal of the square serves as the diameter of the circle, which is 828\sqrt{2} inches. The radius is therefore 424\sqrt{2} inches, and the area of the circle is π(42)2=32π\pi (4\sqrt{2})^2 = 32\pi square inches.

Adım Adım Çözüm

1
Find the side length of the inscribed square from its area.
The side length of the square is 88 inches.
The area of a square is given by s2s^2, where ss is the side length. Since the area is 6464, we solve s2=64s^2 = 64 to find s=8s = 8.
2
Find the length of the diagonal of the square, which represents the diameter of the circle.
The diagonal length is 828\sqrt{2} inches.
In a square with side length ss, the diagonal is s2s\sqrt{2}. Since the square is inscribed in the circle, the diagonal of the square is equal to the diameter of the circle.
3
Calculate the radius of the circle and then the area.
The radius is 424\sqrt{2} inches and the area is 32π32\pi square inches.
The radius rr is half of the diameter, so r=822=42r = \frac{8\sqrt{2}}{2} = 4\sqrt{2}. The area of the circle is given by A=πr2=π(42)2=32πA = \pi r^2 = \pi (4\sqrt{2})^2 = 32\pi.

Anahtar Kavram

Relating the area of an inscribed polygon to the circumscribed circle
Tahmini Süre:1m 30s
Soru 2707Soru

Angle AA has a measure of dd degrees, and angle BB has a measure of rr radians. The sum of the degree measure of angle AA and the degree equivalent of the measure of angle BB is 180180. If the measure of angle AA, in degrees, is 33 times the degree equivalent of the measure of angle BB, and r=kπr = k\pi, what is the value of kk?

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Cevap: 0.25

Cevap

The value of kk is 0.250.25 (or 14\frac{1}{4}).
The correct answer is 0.250.25 (or 14\frac{1}{4}). To find this, we solve the system of equations representing the degree relationship: d+DB=180d + D_B = 180 and d=3DBd = 3D_B, where DBD_B is the degree equivalent of angle BB. This gives DB=45D_B = 45. Converting 4545^\circ to radians by multiplying by π180\frac{\pi}{180} gives π4\frac{\pi}{4} radians, which means the coefficient kk is 0.250.25.

Adım Adım Çözüm

1
Set up a system of equations using the given information.
d+DB=180d + D_B = 180 and d=3DBd = 3D_B, where dd is the degree measure of angle AA and DBD_B is the degree equivalent of angle BB.
To translate the verbal descriptions of the relationships between the angle measures into mathematical equations.
2
Solve the system of equations for DBD_B.
DB=45D_B = 45
Substituting d=3DBd = 3D_B into the first equation yields 3DB+DB=1803D_B + D_B = 180, which simplifies to 4DB=1804D_B = 180. Dividing both sides by 44 gives DB=45D_B = 45.
3
Convert the degree measure of angle BB to radians.
r=π4r = \frac{\pi}{4} radians
To convert degrees to radians, multiply the degree measure by π180\frac{\pi}{180}. This gives 45×π180=π445 \times \frac{\pi}{180} = \frac{\pi}{4}.
4
Find the value of kk from the expression r=kπr = k\pi.
k=0.25k = 0.25 (or 14\frac{1}{4})
Since r=π4=0.25πr = \frac{\pi}{4} = 0.25\pi, comparing this to r=kπr = k\pi shows that k=0.25k = 0.25.

Anahtar Kavram

Converting degrees to radians
Soru 2708Soru

In the xyxy-plane, a circle with its center at the origin O(0,0)O(0,0) is tangent to a line at the point T(3.6,4.8)T(3.6, 4.8). The line intersects the xx-axis at point PP and the yy-axis at point QQ. What is the perimeter of triangle OPQOPQ?

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Cevap: 30.0

Cevap

The perimeter of triangle OPQOPQ is 30.030.0.
The correct answer is 30.0. By finding the distance from the origin to the point of tangency T(3.6,4.8)T(3.6, 4.8), we find the radius is 66. Since the tangent line is perpendicular to this radius, we can determine its equation to be y=0.75x+7.5y = -0.75x + 7.5. The intercepts are P(10,0)P(10,0) and Q(0,7.5)Q(0,7.5), representing the legs of right triangle OPQOPQ. Applying the Pythagorean theorem, the hypotenuse is PQ=102+7.52=12.5PQ = \sqrt{10^2 + 7.5^2} = 12.5. The sum of the sides is 10+7.5+12.5=3010 + 7.5 + 12.5 = 30.

Adım Adım Çözüm

1
Find the radius of the circle, which is the segment OTOT from the origin O(0,0)O(0,0) to the point of tangency T(3.6,4.8)T(3.6, 4.8).
The radius OT=3.62+4.82=12.96+23.04=36=6OT = \sqrt{3.6^2 + 4.8^2} = \sqrt{12.96 + 23.04} = \sqrt{36} = 6.
Since the line is tangent to the circle at TT, the radius OTOT is perpendicular to the tangent line at TT.
2
Find the equation of the tangent line. The slope of the radius OTOT is 4.83.6=43\frac{4.8}{3.6} = \frac{4}{3}.
The slope of the tangent line is the negative reciprocal, 34-\frac{3}{4}. Using the point-slope form with T(3.6,4.8)T(3.6, 4.8), the equation is y4.8=34(x3.6)y - 4.8 = -\frac{3}{4}(x - 3.6), which simplifies to y=0.75x+7.5y = -0.75x + 7.5.
The tangent line is perpendicular to the radius at the point of tangency.
3
Calculate the lengths of the legs of the right triangle OPQOPQ by finding the xx- and yy-intercepts of the tangent line.
Setting y=0y = 0 gives the xx-intercept P(10,0)P(10, 0), so OP=10OP = 10. Setting x=0x = 0 gives the yy-intercept Q(0,7.5)Q(0, 7.5), so OQ=7.5OQ = 7.5.
The vertices PP and QQ lie on the axes, forming a right angle at the origin OO, so OPOP and OQOQ are the legs of right triangle OPQOPQ.
4
Use the Pythagorean theorem to find the length of the hypotenuse PQPQ, and then calculate the perimeter.
PQ=102+7.52=100+56.25=156.25=12.5PQ = \sqrt{10^2 + 7.5^2} = \sqrt{100 + 56.25} = \sqrt{156.25} = 12.5. The perimeter of triangle OPQOPQ is OP+OQ+PQ=10+7.5+12.5=30OP + OQ + PQ = 10 + 7.5 + 12.5 = 30.
The perimeter is the sum of all three side lengths of the right triangle.

Anahtar Kavram

Right Triangles, the Pythagorean Theorem, and Tangent Lines in the Coordinate Plane
Soru 2709Soru

In square ABCDABCD, the side length is 1212. Point EE lies on side ABAB such that AE=3BEAE = 3BE, and point FF lies on side ADAD such that AF=FDAF = FD. What is the area of triangle CEFCEF?

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Cevap: 63

Cevap

63
To find the area of triangle CEFCEF, we subtract the areas of the three right triangles surrounding it from the total area of square ABCDABCD. The area of square ABCDABCD is 122=14412^2 = 144. Point EE on side ABAB splits the side of length 1212 into segments AE=9AE = 9 and BE=3BE = 3. Point FF on side ADAD splits the side of length 1212 into equal segments AF=6AF = 6 and FD=6FD = 6. The areas of the three surrounding right triangles are: Area(AEF)=12×9×6=27\text{Area}(\triangle AEF) = \frac{1}{2} \times 9 \times 6 = 27, Area(EBC)=12×3×12=18\text{Area}(\triangle EBC) = \frac{1}{2} \times 3 \times 12 = 18, and Area(FDC)=12×6×12=36\text{Area}(\triangle FDC) = \frac{1}{2} \times 6 \times 12 = 36. Subtracting these from the total area of the square yields Area(CEF)=144(27+18+36)=14481=63\text{Area}(\triangle CEF) = 144 - (27 + 18 + 36) = 144 - 81 = 63.

Adım Adım Çözüm

1
Determine the lengths of the segments created by points EE and FF on the sides of the square.
Since the square has a side length of 1212, the length of side ABAB is 1212. Given that AE=3BEAE = 3BE and AE+BE=12AE + BE = 12, we can write 3BE+BE=12    4BE=12    BE=33BE + BE = 12 \implies 4BE = 12 \implies BE = 3. This gives AE=9AE = 9. Since FF is the midpoint of ADAD (AF=FDAF = FD), we have AF=FD=122=6AF = FD = \frac{12}{2} = 6.
Finding these segment lengths is necessary to compute the base and height of the right triangles at the corners of the square.
2
Calculate the areas of the three right triangles surrounding triangle CEFCEF.
The area of right triangle AEFAEF is 12×AE×AF=12×9×6=27\frac{1}{2} \times AE \times AF = \frac{1}{2} \times 9 \times 6 = 27. The area of right triangle EBCEBC is 12×BE×BC=12×3×12=18\frac{1}{2} \times BE \times BC = \frac{1}{2} \times 3 \times 12 = 18. The area of right triangle FDCFDC is 12×FD×CD=12×6×12=36\frac{1}{2} \times FD \times CD = \frac{1}{2} \times 6 \times 12 = 36.
These three triangles occupy the entire area of the square except for the region defined by triangle CEFCEF.
3
Subtract the sum of the areas of the three right triangles from the total area of square ABCDABCD.
The total area of square ABCDABCD is 122=14412^2 = 144. The area of triangle CEFCEF is 144(27+18+36)=14481=63144 - (27 + 18 + 36) = 144 - 81 = 63.
This subtraction removes the corner regions, leaving only the area of the central triangle.

Anahtar Kavram

Calculating the area of an inscribed polygon by subtracting the areas of simpler surrounding geometric shapes from a larger bounding shape.

Alternatif Yöntem

Alternatively, coordinate geometry can be used. Place the vertex DD at the origin (0,0)(0,0) on the coordinate plane. Then the coordinates of the vertices of the square are D(0,0)D(0,0), C(12,0)C(12,0), B(12,12)B(12,12), and A(0,12)A(0,12). Point EE lies on segment ABAB and is located at (9,12)(9,12). Point FF lies on segment ADAD and is located at (0,6)(0,6). The area of the triangle with vertices C(12,0)C(12,0), E(9,12)E(9,12), and F(0,6)F(0,6) can be found using the Shoelace Formula: Area=1212(126)+9(60)+0(012)=1272+54+0=12(126)=63\text{Area} = \frac{1}{2} |12(12 - 6) + 9(6 - 0) + 0(0 - 12)| = \frac{1}{2} |72 + 54 + 0| = \frac{1}{2} (126) = 63.
Tahmini Süre:1m 30s
Soru 2710Soru

In the xyxy-plane, an angle θ\theta is in standard position. The terminal ray of the angle is rotated counterclockwise by 7π6\frac{7\pi}{6} radians, and then rotated clockwise by 4545^\circ. If the terminal ray of the resulting angle lies on the positive yy-axis, which of the following could be the value of θ\theta, in degrees?

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Cevap: 285285^\circ

Cevap

The value of θ\theta could be 285285^\circ.
To find the value of θ\theta, we first convert the counterclockwise rotation of 7π6\frac{7\pi}{6} radians into degrees. Multiplying 7π6\frac{7\pi}{6} by 180π\frac{180}{\pi} yields 210210^\circ. A counterclockwise rotation increases the angle measure, so we add 210210^\circ. A clockwise rotation decreases the angle measure, so we subtract 4545^\circ. The resulting angle is θ+21045=θ+165\theta + 210^\circ - 45^\circ = \theta + 165^\circ. Since the terminal ray of the resulting angle lies on the positive yy-axis, it is coterminal with 9090^\circ. Setting θ+165=90+360k\theta + 165^\circ = 90^\circ + 360^\circ k for an integer kk gives θ=75+360k\theta = -75^\circ + 360^\circ k. For k=1k = 1, we get θ=285\theta = 285^\circ, which is the correct value.

Adım Adım Çözüm

1
Convert the counterclockwise rotation from radians to degrees.
7π6×180π=210\frac{7\pi}{6} \times \frac{180}{\pi} = 210^\circ
To work with degrees consistently, we convert the radian measure of the rotation using the conversion factor 180π\frac{180}{\pi}.
2
Set up the equation for the final angle position using the directions of rotation.
Final angle = θ+21045=θ+165\theta + 210^\circ - 45^\circ = \theta + 165^\circ
Counterclockwise rotations are positive (added to θ\theta) and clockwise rotations are negative (subtracted from the result).
3
Relate the final angle to the positive yy-axis and solve for θ\theta.
θ+165=90+360k    θ=75+360k\theta + 165^\circ = 90^\circ + 360^\circ k \implies \theta = -75^\circ + 360^\circ k. For k=1k = 1, θ=285\theta = 285^\circ.
The positive yy-axis corresponds to 9090^\circ in standard position. Solving for θ\theta and adding multiples of 360360^\circ yields the possible measures of the starting angle.

Anahtar Kavram

Converting angle measures between radians and degrees, determining the direction of angular rotation, and finding coterminal angles.
Soru 2711Soru

A student is preparing a presentation on early hominin evidence and has taken the following notes:

* In 1978, paleontologist Mary Leakey discovered fossilized footprints in Laetoli, Tanzania.
* The footprints are preserved in volcanic ash dated to approximately 3.7 million years ago.
* The footprints provide the earliest concrete evidence of upright bipedalism in early hominins.
* The trail consists of footprints made by three individuals of the species *Australopithecus afarensis*.

The student wants to write a sentence that emphasizes both the researcher who discovered the footprints and the approximate age of the footprints. Complete the sentence by filling in the blanks.

Aşağıdaki boşlukları doldurun

Discovered by , the Laetoli footprints date back to .
Cevabı ve açıklamayı göster

Cevap

Discovered by Mary Leakey, the Laetoli footprints date back to approximately 3.7 million years ago.
The completed sentence accurately synthesizes the notes by identifying Mary Leakey as the researcher who discovered the footprints and approximately 3.7 million years ago as the age of the footprints, satisfying both aspects of the rhetorical goal.

Adım Adım Çözüm

1
Identify the researcher who discovered the footprints from the notes.
The notes state that paleontologist Mary Leakey discovered the footprints.
This details the discoverer, fulfilling the first part of the rhetorical goal.
2
Identify the approximate age of the footprints from the notes.
The notes state that the footprints are dated to approximately 3.7 million years ago.
This details the age, fulfilling the second part of the rhetorical goal.
3
Insert the identified details into the corresponding blanks in the sentence.
Blank 1 is filled with 'Mary Leakey' and Blank 2 is filled with 'approximately 3.7 million years ago'.
This completes the sentence while emphasizing the correct details required by the rhetorical goal.

Anahtar Kavram

Synthesizing details from notes to meet a specific rhetorical goal.
Tahmini Süre:1m 0s
Soru 2712Soru

The architectural innovations introduced by the ancient Maya during the Classic period, particularly the vaulted arch, ______ a sophisticated understanding of structural engineering. While modern scholars initially believed these structures were purely ornamental, recent archaeological excavations of residential sites reveal that these advanced building techniques were widely utilized to improve the durability of everyday dwellings.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: demonstrate

Cevap

demonstrate
The plural verb 'demonstrate' correctly agrees in number with the plural subject of the sentence, 'innovations'. The intervening prepositional and appositive phrases, which end with the singular noun 'arch', do not affect the agreement.

Adım Adım Çözüm

1
Identify the subject of the clause containing the blank.
The subject is 'innovations', which is plural.
To ensure subject-verb agreement, the verb must match the number of the true subject, ignoring any intervening modifier phrases.
2
Identify the intervening elements between the subject and the verb.
The phrase 'introduced by the ancient Maya during the Classic period, particularly the vaulted arch' contains the singular noun 'arch'.
Recognizing this intervening modifier prevents the common error of matching the verb with the nearest noun ('arch') instead of the true subject ('innovations').
3
Evaluate the choices to find the plural finite verb.
'demonstrate' is the plural present tense form, which matches 'innovations'.
This establishes grammatical agreement and completes the sentence properly.

Anahtar Kavram

Subject-verb agreement requires a verb to match the grammatical number (singular or plural) of its subject, regardless of any intervening words, phrases, or clauses.
Soru 2713Soru

While preparing a presentation on the Rosetta Stone, a student took the following notes:
* The Rosetta Stone is an ancient Egyptian stele discovered in 17991799.
* It is made of granodiorite, a coarse-grained igneous rock.
* The stone features a decree issued at Memphis in 196 BCE196\text{ BCE} on behalf of King Ptolemy V.
* The decree is written in three distinct scripts: Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek.
* French scholar Jean-François Champollion deciphered the hieroglyphs in 18221822.

The student wants to emphasize the physical material of the Rosetta Stone and the scripts used in its inscriptions. Which choice most effectively uses information from the given notes to accomplish this goal?

Cevabı ve açıklamayı göster

Cevap: The Rosetta Stone, which is made of granodiorite, features a decree inscribed in Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek.

Cevap

The correct answer is the option stating that the Rosetta Stone is made of granodiorite and features a decree inscribed in Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek.
The correct answer successfully meets the student's goal by identifying the physical material of the stone (granodiorite) and naming the three scripts used in the inscription (Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek).

Adım Adım Çözüm

1
Identify the student's specific rhetorical goal in the prompt.
The goal is to emphasize both the physical material of the Rosetta Stone and the scripts used in its inscriptions.
This establishes the criteria that the correct option must satisfy.
2
Locate the relevant details in the provided bulleted notes.
The material is granodiorite, and the three scripts are Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek.
This identifies the specific factual information that must be present in the correct option.
3
Evaluate the choices to find the one that includes these specific details and directly addresses the goal.
The choice that states the stone is made of granodiorite and inscribed in Ancient Egyptian hieroglyphs, Demotic script, and Ancient Greek is the only one that meets all criteria accurately.
This eliminates options that neglect the goal, misrepresent the facts, or make unsupported inferences.

Anahtar Kavram

Rhetorical Synthesis: Emphasizing Specific Details
Soru 2714Soru

In the xyxy-plane, the line y=mxy = mx, where mm is a positive constant, is tangent to the circle defined by the equation x2+y26x8y+16=0x^2 + y^2 - 6x - 8y + 16 = 0. What is the value of mm?

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Cevap: 724\frac{7}{24}

Cevap

724\frac{7}{24}
The correct answer is 724\frac{7}{24}. Standardizing the circle equation gives (x3)2+(y4)2=9(x-3)^2 + (y-4)^2 = 9, identifying the center as (3,4)(3, 4) and the radius as 33. A line mxy=0mx - y = 0 is tangent to the circle if the distance from (3,4)(3, 4) to the line is 33. Applying the distance formula yields 3m4m2+1=3\frac{|3m - 4|}{\sqrt{m^2 + 1}} = 3, which simplifies to m=724m = \frac{7}{24} after squaring and solving for mm.

Adım Adım Çözüm

1
Complete the square for the circle's equation to find the center and radius.
The given equation x2+y26x8y+16=0x^2 + y^2 - 6x - 8y + 16 = 0 can be rewritten as (x3)29+(y4)216+16=0(x-3)^2 - 9 + (y-4)^2 - 16 + 16 = 0, which simplifies to (x3)2+(y4)2=9(x-3)^2 + (y-4)^2 = 9. Thus, the circle has center (3,4)(3, 4) and radius r=9=3r = \sqrt{9} = 3.
Converting the general form equation of a circle to standard form is necessary to find the coordinates of its center and its radius.
2
Set up the equation for the distance from the center of the circle to the tangent line.
The line is given by y=mxy = mx, which can be written in standard form as mxy=0mx - y = 0. The perpendicular distance from the center (3,4)(3, 4) to this line must equal the circle's radius 33. Using the point-to-line distance formula: m(3)(4)m2+(1)2=3\frac{|m(3) - (4)|}{\sqrt{m^2 + (-1)^2}} = 3.
A line is tangent to a circle if and only if the perpendicular distance from the center of the circle to the line is equal to the radius.
3
Solve the distance equation for the constant mm.
3m4=3m2+1|3m - 4| = 3\sqrt{m^2 + 1}. Squaring both sides gives (3m4)2=9(m2+1)9m224m+16=9m2+9(3m - 4)^2 = 9(m^2 + 1) \Rightarrow 9m^2 - 24m + 16 = 9m^2 + 9. Subtracting 9m29m^2 from both sides gives 24m+16=924m=7m=724-24m + 16 = 9 \Rightarrow 24m = 7 \Rightarrow m = \frac{7}{24}.
Squaring both sides eliminates the absolute value and the radical, allowing us to isolate and solve for mm algebraically.

Anahtar Kavram

Equations of circles and the relationship between a circle and its tangent lines in the coordinate plane

Alternatif Yöntem

The problem can also be solved using geometry and right-triangle trigonometry. The distance from the origin O(0,0)O(0,0) to the center C(3,4)C(3,4) is 55. The radius to the point of tangency TT is 33, forming a right triangle OTCOTC with hypotenuse OC=5OC = 5 and leg CT=3CT = 3. The other leg is OT=4OT = 4. The angle θ\theta that OCOC makes with the positive xx-axis has tanθ=43\tan\theta = \frac{4}{3}, and the angle α\alpha between OCOC and OTOT has tanα=34\tan\alpha = \frac{3}{4}. The slope of the tangent line OTOT is m=tan(θα)m = \tan(\theta - \alpha). Applying the tangent subtraction formula tan(θα)=tanθtanα1+tanθtanα\tan(\theta - \alpha) = \frac{\tan\theta - \tan\alpha}{1 + \tan\theta\tan\alpha} gives m=724m = \frac{7}{24}.
Tahmini Süre:3m 0s
Soru 2715Soru

In historical musicology, the dissemination of hand-copied musical manuscripts across various European courts during the early Baroque period ______ how stylistic trends spread independently of published compositions. While printed books were highly expensive and difficult to distribute, these informal manuscript copies allowed composers to share their work rapidly with peers across borders. Consequently, regional variations developed much faster than previously assumed.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: illustrates

Cevap

The singular verb 'illustrates' correctly agrees with the singular subject 'dissemination'.
The singular verb 'illustrates' correctly agrees with the singular subject of the sentence, 'dissemination'. The intervening prepositional phrase containing the plural nouns 'manuscripts' and 'courts' does not change the singular nature of the subject.

Adım Adım Çözüm

1
Identify the subject of the verb in the sentence.
The subject is the singular noun 'dissemination'. The prepositional phrase 'of hand-copied musical manuscripts across various European courts during the early Baroque period' is an intervening phrase and does not affect the number of the subject.
A verb must agree in number with its grammatical subject, ignoring any intervening prepositional modifiers.
2
Select the correct singular verb form that maintains consistency.
The singular present-tense verb 'illustrates' is chosen.
The sentence presents a general historical fact, requiring a singular present-tense verb to match the singular subject 'dissemination'.

Anahtar Kavram

A verb must agree in number with its subject, even when separated by intervening prepositional phrases or clauses containing nouns of a different number.
Soru 2716Soru

In the xyxy-plane, the graph of the equation 3x2+3y224x+18yc=03x^2 + 3y^2 - 24x + 18y - c = 0, where cc is a constant, represents a circle. If the area of the circle is 100π100\pi, what is the value of cc?

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Cevap: 225

Cevap

225
The correct answer is 225. Dividing the given equation 3x2+3y224x+18yc=03x^2 + 3y^2 - 24x + 18y - c = 0 by 3 gives x2+y28x+6yc3=0x^2 + y^2 - 8x + 6y - \frac{c}{3} = 0. Completing the square for the xx-terms by adding (8/2)2=16(-8/2)^2 = 16 and for the yy-terms by adding (6/2)2=9(6/2)^2 = 9 to both sides results in (x4)2+(y+3)2=c3+25(x - 4)^2 + (y + 3)^2 = \frac{c}{3} + 25. The standard equation of a circle is (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2, where rr is the radius. Since the area of the circle is 100π100\pi and the area formula is A=πr2A = \pi r^2, the radius squared r2r^2 must equal 100. Setting the right-hand side of our standard form equation equal to 100 gives c3+25=100\frac{c}{3} + 25 = 100. Solving for cc yields c3=75\frac{c}{3} = 75, which gives c=225c = 225.

Adım Adım Çözüm

1
Divide the entire equation by the coefficient of the squared terms to normalize it.
x2+y28x+6yc3=0x^2 + y^2 - 8x + 6y - \frac{c}{3} = 0
The standard form of a circle's equation requires the coefficients of x2x^2 and y2y^2 to be 1.
2
Complete the square for both the xx and yy terms.
(x28x+16)+(y2+6y+9)=c3+16+9(x^2 - 8x + 16) + (y^2 + 6y + 9) = \frac{c}{3} + 16 + 9, which simplifies to (x4)2+(y+3)2=c3+25(x - 4)^2 + (y + 3)^2 = \frac{c}{3} + 25
Completing the square converts the general equation of a circle into the standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2.
3
Use the given area of the circle to determine the radius squared, r2r^2.
r2=100r^2 = 100
The area of a circle is defined by A=πr2A = \pi r^2. Given that the area is 100π100\pi, we have πr2=100π\pi r^2 = 100\pi, which means r2=100r^2 = 100.
4
Equate the expression for r2r^2 from the standard form to the value found from the area and solve for cc.
c3+25=100c3=75c=225\frac{c}{3} + 25 = 100 \Rightarrow \frac{c}{3} = 75 \Rightarrow c = 225
From the standard form, the right-hand side is equal to r2r^2. Equating the two expressions allows us to solve for the constant cc.

Anahtar Kavram

To find the radius or related constants of a circle from its general equation, first divide by any common coefficient of the squared terms, then complete the square to write the equation in the standard form (xh)2+(yk)2=r2(x - h)^2 + (y - k)^2 = r^2.
Soru 2717Soru

In a circle with center OO, the central angle AOBAOB has a measure of 4π5\frac{4\pi}{5} radians. Angle BOCBOC is adjacent to angle AOBAOB such that they form a straight line. What is the degree measure of angle BOCBOC?

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Cevap: 36

Cevap

The degree measure of angle BOCBOC is 36.
Angles AOBAOB and BOCBOC form a straight line, which means they are supplementary and their measures add up to 180180^\circ (or π\pi radians). Since angle AOBAOB measures 4π5\frac{4\pi}{5} radians, we can convert this measure to degrees first by multiplying by 180π\frac{180^\circ}{\pi}: 4π5×180π=4×36=144\frac{4\pi}{5} \times \frac{180^\circ}{\pi} = 4 \times 36^\circ = 144^\circ. To find the degree measure of the supplementary angle BOCBOC, subtract 144144^\circ from 180180^\circ, giving 180144=36180^\circ - 144^\circ = 36^\circ. Alternatively, the calculation can be performed in radians first: π4π5=π5\pi - \frac{4\pi}{5} = \frac{\pi}{5} radians, and then converting π5\frac{\pi}{5} radians to degrees: π5×180π=36\frac{\pi}{5} \times \frac{180^\circ}{\pi} = 36^\circ.

Adım Adım Çözüm

1
Identify the relationship between the two adjacent angles.
The sum of the measures of angles AOBAOB and BOCBOC is π\pi radians or 180180^\circ.
Since the adjacent angles AOBAOB and BOCBOC form a straight line, they are supplementary.
2
Calculate the measure of angle BOCBOC in radians.
Angle BOCBOC measures π5\frac{\pi}{5} radians.
Subtract the measure of angle AOBAOB from the straight line measure: π4π5=π5\pi - \frac{4\pi}{5} = \frac{\pi}{5} radians.
3
Convert the radian measure of angle BOCBOC to degrees.
The degree measure is 36.
Multiply the radian measure by the conversion factor 180π\frac{180^\circ}{\pi}: π5×180π=36\frac{\pi}{5} \times \frac{180}{\pi} = 36^\circ.

Anahtar Kavram

Converting angles from radians to degrees and using the properties of supplementary angles.
Soru 2718Soru

For triangle ABCABC, points DD and EE are on sides ABAB and ACAC, respectively, such that segment DEDE is parallel to segment BCBC. If the length of segment ADAD is x+5x + 5, the length of segment DBDB is 66, the length of segment AEAE is x2x - 2, and the length of segment ECEC is 33. What is the length of segment AEAE?

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Cevap: 7

Cevap

7
According to the Triangle Proportionality Theorem, since segment DEDE is parallel to segment BCBC, the sides of triangle ABCABC are divided proportionally: ADDB=AEEC\frac{AD}{DB} = \frac{AE}{EC}. Substituting the given expressions, we get x+56=x23\frac{x+5}{6} = \frac{x-2}{3}. Multiplying both sides of the equation by 6 gives x+5=2(x2)x+5 = 2(x-2). Distributing the 2 to both terms inside the parentheses yields x+5=2x4x+5 = 2x-4. Subtracting xx from both sides gives 5=x45 = x-4, and adding 4 to both sides gives x=9x = 9. The question asks for the length of segment AEAE, which is defined as x2x-2. Substituting x=9x = 9 into this expression gives 92=79 - 2 = 7.

Adım Adım Çözüm

1
Identify the relationship between the triangles and set up the proportion.
Since DEBCDE \parallel BC, triangle ADEADE is similar to triangle ABCABC (ADEABC\triangle ADE \sim \triangle ABC). By the Triangle Proportionality Theorem, this gives the proportion ADDB=AEEC\frac{AD}{DB} = \frac{AE}{EC}.
A line parallel to one side of a triangle divides the other two sides proportionally.
2
Substitute the given side lengths into the proportion.
x+56=x23\frac{x+5}{6} = \frac{x-2}{3}
Using the algebraic expressions provided in the problem statement.
3
Solve the equation for xx.
Multiplying both sides by 6 gives x+5=2(x2)x+5 = 2(x-2). Distributing the 2 gives x+5=2x4x+5 = 2x-4. Subtracting xx and adding 4 to both sides yields x=9x = 9.
To determine the value of the variable xx.
4
Calculate the length of segment AEAE.
AE=x2=92=7AE = x - 2 = 9 - 2 = 7.
The question asks for the length of segment AEAE, so we substitute x=9x = 9 back into the expression for AEAE.

Anahtar Kavram

Using the Triangle Proportionality Theorem and properties of similar triangles to solve for unknown side lengths using algebraic expressions.
Tahmini Süre:1m 30s
Soru 2719Soru

In computational linguistics, researchers analyze how digital text corpora evolve over generations. The semantic mapping of obscure dialects—which often relies on machine learning models trained on limited historical texts—______ a unique opportunity to study linguistic drift in real time. By tracing subtle shifts in word usage across decades, scholars can better understand how geographical isolation and cultural exchanges shape modern vocabulary.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: presents

Cevap

The verb 'presents', which is singular and present tense, correctly matches the singular subject 'mapping'.
The singular, present-tense verb 'presents' correctly agrees in number with the singular subject 'the semantic mapping'. The intervening clause ('which often relies on machine learning models...') describes the subject but does not change its number.

Adım Adım Çözüm

1
Identify the subject of the sentence containing the blank.
The subject is the singular noun phrase 'the semantic mapping'.
Subject-verb agreement requires identifying the true subject of the clause, ignoring any intervening descriptive phrases or clauses.
2
Analyze the intervening element between the subject and the verb.
The clause '—which often relies on machine learning models trained on limited historical texts—' is a nonessential modifier containing plural nouns ('dialects', 'models', 'texts').
These plural nouns can distract from the singular subject 'mapping'.
3
Select the verb form that agrees with the singular subject and fits the context.
The singular verb 'presents' correctly agrees with the singular subject 'mapping' and provides a finite verb to complete the clause.
The other options either use plural verb forms or a non-finite participle, violating subject-verb agreement or creating a sentence fragment.

Anahtar Kavram

Subject-Verb Agreement with Intervening Phrases
Soru 2720Soru

Many marine phytoplankton species rely on dissolved iron to synthesize chlorophyll for photosynthesis. In the Southern Ocean, low iron concentrations typically limit phytoplankton growth. However, researchers observed rapid increases in phytoplankton blooms during periods of high continental dust deposition. Some scientists hypothesized that the dust directly supplies iron to the water, while others proposed that the dust stimulates local iron-producing bacteria. Analyses of the dust revealed that it releases highly bioavailable iron upon contacting seawater, whereas local bacterial populations showed no change in density or activity during the blooms.

Which choice most logically completes the text?

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Cevap: The increase in phytoplankton blooms is primarily driven by the iron directly released from the dust rather than by the activity of local bacteria.

Cevap

The increase in phytoplankton blooms is primarily driven by the iron directly released from the dust rather than by the activity of local bacteria.
The correct answer logically completes the text because the passage sets up two possible explanations for why dust deposition increases phytoplankton blooms: direct supply of iron by the dust, or stimulation of iron-producing bacteria. Since the dust was shown to release iron directly and the bacteria showed no changes in activity or density, the evidence supports the direct-supply hypothesis and refutes the bacterial-stimulation hypothesis.

Adım Adım Çözüm

1
Identify the two competing hypotheses presented in the passage.
The first hypothesis states that dust directly supplies iron to the Southern Ocean. The second hypothesis states that dust stimulates local bacteria to produce iron.
This establishes the framework of the arguments that need to be evaluated.
2
Analyze the experimental findings and evidence provided.
The dust releases bioavailable iron when it contacts seawater, but the local bacterial populations showed no change in density or activity.
This evidence allows us to determine which hypothesis is supported and which is undermined.
3
Select the option that logically follows from the evidence.
Since the dust directly releases iron and the bacteria are unaffected, the bloom must be driven directly by the iron from the dust, not by the bacteria.
This completes the logical chain and yields the correct inference.

Anahtar Kavram

Drawing logical conclusions that are directly supported by premises in the text and evaluating competing hypotheses based on evidence.
Tahmini Süre:1m 30s
ÖncekiSayfa 136 / 140Sonraki
Tüm alıştırma soruları — SAT | Examkin