Tüm alıştırma soruları

2789 soru

Soru 2501Soru

A straight ladder is leaning against a vertical wall. The base of the ladder is placed 99 feet from the bottom of the wall. If the top of the ladder touches the wall at a height of 1212 feet above the ground, what is the length, in feet, of the ladder?

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Cevap: 15

Cevap

The length of the ladder is 1515 feet.
By representing the scenario as a right triangle, the two perpendicular sides (legs) have lengths of 99 feet and 1212 feet. Using the Pythagorean theorem (a2+b2=c2a^2 + b^2 = c^2), we find 92+122=81+144=2259^2 + 12^2 = 81 + 144 = 225. Taking the square root of 225225 gives the hypotenuse length, which is 1515 feet.

Adım Adım Çözüm

1
Model the scenario using a right triangle.
A right triangle where the vertical leg is 1212 feet (height on the wall), the horizontal leg is 99 feet (distance along the ground), and the hypotenuse is cc (the ladder length).
The intersection of the vertical wall and the horizontal ground forms a right angle (9090^\circ).
2
Set up the Pythagorean equation.
92+122=c29^2 + 12^2 = c^2
The Pythagorean theorem states that the sum of the squares of the legs of a right triangle equals the square of the hypotenuse.
3
Solve for the hypotenuse cc.
c=81+144=225=15c = \sqrt{81 + 144} = \sqrt{225} = 15
Simplifying the arithmetic yields 225225, and taking the square root gives the final length of 1515 feet.

Anahtar Kavram

Pythagorean Theorem
Tahmini Süre:45s
Soru 2502Soru

While researching bioacoustics, a student takes the following notes:
* Blue whales (*Balaenoptera musculus*) use low-frequency vocalizations to communicate across vast ocean distances.
* In a 20182018 study, researchers analyzed underwater audio recordings of blue whale songs collected from 19601960 to 20182018.
* The analysis revealed that the fundamental frequency of blue whale songs has decreased by approximately 30%30\% globally.
* Researchers hypothesize that this pitch reduction is an adaptation to cope with rising ambient ocean noise caused by commercial shipping.

The student wants to summarize the study's findings. Which choice most effectively uses information from the given notes to accomplish this goal?

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Cevap: An analysis of audio recordings from 19601960 to 20182018 revealed that blue whales have reduced the pitch of their songs by about 30%30\% globally, likely to communicate over rising shipping noise.

Cevap

The choice stating that an analysis of recordings from 19601960 to 20182018 revealed a global pitch decrease of about 30%30\%, likely to communicate over shipping noise, is correct because it summarizes both the finding and its hypothesized cause.
The correct answer effectively summarizes the findings of the study by stating that the analysis of recordings from 19601960 to 20182018 showed a global 30%30\% reduction in the pitch of blue whale songs, and by presenting the hypothesis that this change helps them communicate over shipping noise.

Adım Adım Çözüm

1
Identify the student's specific rhetorical goal in the prompt.
The goal is to summarize the findings of the 2018 study.
Understanding the exact goal helps eliminate choices that focus on background context or methodology rather than the results.
2
Analyze the notes to determine what findings the study produced.
The findings are that blue whale songs have decreased in pitch by approximately 30%30\% globally, which is hypothesized to be an adaptation to shipping noise.
Knowing the specific findings allows for comparison with the options to see which one accurately presents this information.
3
Evaluate the options to find the one that summarizes these findings without adding outside information or ignoring the goal.
The option mentioning the 30%30\% reduction in pitch and the shipping noise explanation is the only choice that directly summarizes the findings.
This choice satisfies the rhetorical goal, while others either focus on methodology, background information, or make unsupported claims.

Anahtar Kavram

Summarization and Generalization in Rhetorical Synthesis
Soru 2503Soru

Paleontologists studying the fossilization of soft-bodied organisms from the Burgess Shale have noted that specific chemical microenvironments are required to prevent decay before mineralization can occur. ______ extremely low oxygen levels in the sediment can inhibit the activity of aerobic decomposers, allowing delicate structures like gills and antennae to be preserved.

Which choice completes the text with the most logical transition?

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Cevap: Specifically,

Cevap

Specifically
The correct option is 'Specifically' because the first sentence discusses the general necessity of 'specific chemical microenvironments' for soft-tissue fossilization, and the second sentence details a particular instance of such a microenvironment—namely, low oxygen levels in the sediment that inhibit decomposers. Therefore, the transition logically introduces this specific elaboration.

Adım Adım Çözüm

1
Analyze the relationship between the two sentences.
The first sentence introduces a general claim that 'specific chemical microenvironments' are needed to preserve soft-bodied fossils. The second sentence describes a particular condition ('extremely low oxygen levels in the sediment') and explains how it helps with preservation.
Understanding how the second sentence relates to the first is key to identifying the correct transition type.
2
Identify the type of logical connection.
Since the second sentence provides a specific example and elaboration of the general term 'chemical microenvironments' mentioned in the first sentence, an elaboration or exemplification transition is needed.
This helps narrow down the choices to words that signal exemplification or elaboration, such as 'Specifically'.
3
Evaluate the choices against this logical relationship.
'Conversely' introduces contrast, which is incorrect. 'Consequently' indicates cause-and-effect, which is incorrect. 'Previously' indicates a temporal sequence, which is incorrect. 'Specifically' correctly signals that the second sentence details the general concept from the first.
Evaluating each option ensures that distractors are systematically eliminated based on grammatical or logical misalignment.

Anahtar Kavram

Transitions: Elaboration and Exemplification
Tahmini Süre:1m 0s
Soru 2504Soru

In subglacial lakes beneath the Antarctic Ice Sheet, primary production cannot rely on photosynthesis due to the absolute absence of sunlight. Instead, chemosynthetic microbes oxidize inorganic compounds, such as iron or sulfur, to generate energy. In Lake Mercer, researchers discovered high concentrations of dissolved organic carbon (DOC) alongside these chemosynthetic communities. Because the ice sheet has isolated the lake from the atmosphere for thousands of years, this DOC cannot have originated from recent photosynthetic activity. However, analysis revealed that the DOC molecules are structurally similar to those produced by marine phytoplankton, which require sunlight. Which choice most logically completes the text?

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Cevap: the dissolved organic carbon currently in the lake is likely ancient material that was deposited before the ice sheet isolated the lake from the ocean.

Cevap

The dissolved organic carbon currently in the lake is likely ancient material that was deposited before the ice sheet isolated the lake from the ocean.
The correct option logically completes the passage by explaining the origin of the dissolved organic carbon (DOC) in Lake Mercer. Since the lake has been isolated for thousands of years, the DOC cannot be from recent photosynthetic activity. However, because the DOC is structurally similar to that produced by marine phytoplankton (which require sunlight), it must have been deposited during a past period when the area was connected to the ocean and exposed to sunlight, before the ice sheet isolated it.

Adım Adım Çözüm

1
Identify the premises regarding Lake Mercer's environmental conditions and findings.
The lake is isolated from the atmosphere and sunlight, meaning no recent photosynthesis occurs. Chemosynthetic microbes generate energy from inorganic compounds, yet the lake has a high concentration of dissolved organic carbon (DOC) that is structurally similar to DOC produced by marine phytoplankton.
This establishes the constraints: the DOC must have a source, but it cannot be from recent photosynthesis or from the chemosynthetic microbes' primary energy generation.
2
Analyze the structural similarity of the DOC to marine phytoplankton.
Since marine phytoplankton require sunlight, and the lake is currently dark and isolated, the phytoplankton must have produced this DOC when the region was connected to the marine environment.
This connects the marine origin of the DOC with the historical state of the lake before isolation.
3
Evaluate the choices to find the one that logically completes the explanation of the DOC's presence without introducing outside assumptions.
The conclusion that the DOC is ancient material deposited before isolation is the only direct, non-speculative option supported by all premises.
This completes the logical chain: ancient marine deposition explains both the phytoplankton structure and the lack of recent photosynthetic sources.

Anahtar Kavram

Logical Inferences
Tahmini Süre:1m 30s
Soru 2505Soru

Historically, geologists characterized the Earth’s mantle as a largely homogenous and static layer of solid rock. However, recent high-resolution seismic imaging has ________ this traditional model, revealing complex, localized convection currents and composition gradients that indicate a far more dynamic interior.

Which choice completes the text with the most logical and precise word or phrase?

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Cevap: challenged

Cevap

challenged
The context describes a contrast between the historical view of the Earth's mantle as 'homogenous and static' and the new findings of 'complex, localized convection currents' indicating a 'far more dynamic interior.' The transition word 'However' signals this contrast. The word 'challenged' precisely fits this context because it means to dispute or call into question, reflecting how the new seismic imaging contradicts the traditional model.

Adım Adım Çözüm

1
Analyze the context of the sentence and the role of the blank.
The blank requires a verb that describes the impact of new seismic imaging on the traditional model of a homogenous, static mantle.
Understanding the sentence structure and the relationship between ideas is necessary to identify the correct meaning.
2
Identify transition words and contrasting ideas.
The transition word 'However' and the description of the new findings ('complex, localized convection currents') contrast with the 'homogenous and static' traditional model.
This contrast signals that the new imaging contradicts or calls into question the traditional model, requiring a word with a similar meaning.
3
Evaluate the answer choices based on the context.
'Challenged' fits because it means to dispute, while 'corroborated' has the opposite meaning, and 'predicted' and 'overlooked' are logically inappropriate.
This eliminates the distractors and confirms the correct choice.

Anahtar Kavram

Words in Context: High-Utility Vocabulary
Tahmini Süre:1m 0s
Soru 2506Soru

In marine ecology, the term "kleptoplasty" describes a symbiotic phenomenon where a host organism sequesters functional chloroplasts from digested algae and uses them to perform photosynthesis. ______ the sea slug *Elysia chlorotica* feeds on the alga *Vaucheria litorea* and is subsequently able to survive for months solely on the energy produced by these stolen organelles.

Which choice completes the passage with the most logical transition?

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Cevap: In fact,

Cevap

The transition 'In fact' logically connects the general definition of kleptoplasty to the specific example of the sea slug *Elysia chlorotica*.
The transition 'In fact' logically connects the two sentences. The first sentence defines the general biological phenomenon of kleptoplasty, in which an organism captures and uses chloroplasts from algae. The second sentence provides a specific example of this process in action: the sea slug *Elysia chlorotica* feeding on alga and utilizing its chloroplasts to survive. 'In fact' is used to introduce an elaboration or specific instance of a previously stated concept, making it the most logical fit.

Adım Adım Çözüm

1
Analyze the relationship between the two sentences.
The first sentence defines the general concept of kleptoplasty, and the second sentence provides a specific example (*Elysia chlorotica*) of this phenomenon.
Understanding the logical connection between the ideas is essential for choosing the correct transition.
2
Determine the type of transition required.
Since the second sentence exemplifies or elaborates on the first, a transition of elaboration or exemplification is needed.
The correct transition must reflect this continuous, illustrative relationship.
3
Evaluate the choices against the required transition type.
'In fact' is the only option that functions as an elaboration or exemplification transition.
Other options introduce incorrect logical relationships such as cause-and-effect, contrast, or simple addition.

Anahtar Kavram

Transitions: Elaboration and Exemplification
Soru 2507Soru

A small design firm employs 1010 people. The mean of their annual salaries is $50,000\$50,000, and the median is $48,000\$48,000. The employee with the highest salary of $95,000\$95,000 receives a $10,000\$10,000 raise, while the salaries of all other employees remain unchanged. What are the mean and the median of the salaries after the raise?

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Cevap: Mean: $51,000\$51,000; Median: $48,000\$48,000

Cevap

The new mean salary is $51,000\$51,000 and the new median salary is $48,000\$48,000.
The correct option correctly identifies that the mean salary increases to $51,000\$51,000 and the median salary remains at $48,000\$48,000. Since the sum of the salaries increases by $10,000\$10,000 and there are 1010 employees, the mean increases by $10,000÷10=$1,000\$10,000 \div 10 = \$1,000, resulting in a new mean of $51,000\$51,000. Because the raise is given to the employee who already earns the highest salary, the sorted order of the salaries is unaffected, meaning the middle values remain unchanged, so the median remains $48,000\$48,000.

Adım Adım Çözüm

1
Calculate the new mean salary by finding the effect of the salary raise on the average.
The total sum of all salaries increases by $10,000\$10,000. Since there are 1010 employees, the mean salary increases by $10,00010=$1,000\frac{\$10,000}{10} = \$1,000. Therefore, the new mean is $50,000+$1,000=$51,000\$50,000 + \$1,000 = \$51,000.
The mean is calculated as the sum of all values divided by the number of values. A change in the sum changes the mean proportionally.
2
Determine the new median salary by analyzing if the order of the dataset has changed.
The raise is given to the employee who already has the highest salary of $95,000\$95,000. Since this remains the highest salary (now $105,000\$105,000), the sorted order of the 1010 salaries does not change. The median is the average of the 5th and 6th values in the sorted list, which remain unchanged. Thus, the median remains $48,000\$48,000.
The median represents the middle value of a sorted dataset and is insensitive to changes in extreme values that do not alter the sorted sequence.

Anahtar Kavram

Understanding how individual data point adjustments affect the mean and median of a distribution.
Soru 2508Soru

The function gg is defined by g(x)=f(x3)2g(x) = f(x - 3) - 2. If the point (5,7)(5, 7) lies on the graph of y=f(x)y = f(x) in the xyxy-plane, which of the following points must lie on the graph of y=g(x)y = g(x)?

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Cevap: (8,5)(8, 5)

Cevap

The point (8,5)(8, 5)
The transformation g(x)=f(x3)2g(x) = f(x - 3) - 2 shifts the graph of f(x)f(x) to the right by 3 units and down by 2 units. Therefore, the x-coordinate of the point (5,7)(5, 7) increases by 3 (5+3=85 + 3 = 8), and the y-coordinate decreases by 2 (72=57 - 2 = 5). This determines that the point (8,5)(8, 5) must lie on the graph of y=g(x)y = g(x).

Adım Adım Çözüm

1
Identify the horizontal and vertical transformations applied to the function f(x)f(x) to get g(x)g(x).
The graph of g(x)=f(x3)2g(x) = f(x - 3) - 2 is translated horizontally to the right by 3 units and vertically down by 2 units relative to the graph of f(x)f(x).
By function transformation rules, f(xh)+kf(x - h) + k translates the graph horizontally by hh units (right if h>0h > 0) and vertically by kk units (up if k>0k > 0).
2
Calculate the new x-coordinate for the point on the transformed graph.
The new x-coordinate is 5+3=85 + 3 = 8.
Translating the graph to the right by 3 units increases all x-coordinates of points on the graph by 3.
3
Calculate the new y-coordinate for the point on the transformed graph.
The new y-coordinate is 72=57 - 2 = 5.
Translating the graph down by 2 units decreases all y-coordinates of points on the graph by 2.

Anahtar Kavram

Function notation and translations in the coordinate plane
Tahmini Süre:1m 15s
Soru 2509Soru

The table below shows several values of xx and the corresponding values of the third-degree polynomial function ff.

xxf(x)f(x)
1-100
2200
5500
003030

If f(x)=a(xr1)(xr2)(xr3)f(x) = a(x-r_1)(x-r_2)(x-r_3) for all real numbers xx, where aa, r1r_1, r2r_2, and r3r_3 are constants, what is the value of aa?

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Cevap: 3

Cevap

3
Since the function f(x)f(x) is a third-degree polynomial with roots at x=1x = -1, x=2x = 2, and x=5x = 5, it can be factored as f(x)=a(x+1)(x2)(x5)f(x) = a(x+1)(x-2)(x-5). Evaluating this expression at x=0x = 0 gives f(0)=a(1)(2)(5)=10af(0) = a(1)(-2)(-5) = 10a. From the table, f(0)=30f(0) = 30, so setting 10a=3010a = 30 yields a=3a = 3.

Adım Adım Çözüm

1
Identify the roots and factors of the polynomial f(x)f(x) using the table.
The roots are x=1x = -1, x=2x = 2, and x=5x = 5, which correspond to the factors (x+1)(x+1), (x2)(x-2), and (x5)(x-5).
Points where f(x)=0f(x) = 0 represent the xx-intercepts (roots) of the function.
2
Write the general form of the cubic polynomial using its factors.
f(x)=a(x+1)(x2)(x5)f(x) = a(x+1)(x-2)(x-5)
A third-degree polynomial with three distinct real roots can be factored completely as a(xr1)(xr2)(xr3)a(x-r_1)(x-r_2)(x-r_3).
3
Substitute the point (0,30)(0, 30) into the equation to solve for the constant coefficient aa.
a=3a = 3
The table gives f(0)=30f(0) = 30, which allows us to set up the equation 30=a(0+1)(02)(05)30 = a(0+1)(0-2)(0-5) and solve for aa.

Anahtar Kavram

Using the relationship between the factors, roots, and points on the graph of a polynomial function to determine its equation.
Soru 2510Soru

In triangle ABCABC, point DD lies on side BCBC such that the ratio of BDBD to DCDC is 11 to 22. Point EE lies on segment ADAD such that the ratio of AEAE to EDED is 33 to 11. A line passing through EE and parallel to ACAC intersects side ABAB at FF and side BCBC at GG. If the area of triangle ABCABC is 128128, what is the area of triangle BFGBFG?

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Cevap: 32

Cevap

32
The correct answer is 32. By establishing a coordinate system, we find that the similarity ratio of triangle BFGBFG to triangle ABCABC is exactly 1/21/2 regardless of the triangle's shape. Since the ratio of the areas of similar triangles is the square of the similarity ratio, the area of triangle BFGBFG is (1/2)2=1/4(1/2)^2 = 1/4 of the area of triangle ABCABC, which is 128×1/4=32128 \times 1/4 = 32.

Adım Adım Çözüm

1
Set up a coordinate system to represent the triangle's vertices.
Let B=(0,0)B = (0, 0) and C=(3,0)C = (3, 0). Since DD lies on side BCBC and BD:DC=1:2BD:DC = 1:2, the coordinates of DD are (1,0)(1, 0). Let A=(a,b)A = (a, b).
Setting up coordinates simplifies the proof by allowing algebraic verification of the ratio.
2
Calculate the coordinates of point EE on segment ADAD.
Using the section formula with ratio AE:ED=3:1AE:ED = 3:1, E=(1(a)+3(1)4,1(b)+3(0)4)=(a+34,b4)E = \left(\frac{1(a) + 3(1)}{4}, \frac{1(b) + 3(0)}{4}\right) = \left(\frac{a+3}{4}, \frac{b}{4}\right).
Finding the coordinates of EE is necessary to determine the equation of line FGFG.
3
Find the equation of line FGFG which is parallel to ACAC and passes through EE.
The slope of ACAC is m=b3am = \frac{-b}{3-a}. The equation of FGFG is yb4=b3a(xa+34)y - \frac{b}{4} = \frac{-b}{3-a}\left(x - \frac{a+3}{4}\right).
The line FGFG is parallel to ACAC, meaning they share the same slope.
4
Find the coordinates of GG by setting y=0y = 0 in the equation of FGFG.
Setting y=0y = 0 yields b4=b3a(xGa+34)    xG=1.5-\frac{b}{4} = \frac{-b}{3-a}\left(x_G - \frac{a+3}{4}\right) \implies x_G = 1.5. Thus, G=(1.5,0)G = (1.5, 0).
Point GG is the intersection of the line FGFG with side BCBC (the x-axis).
5
Determine the similarity ratio and calculate the area of triangle BFGBFG.
Since GG is the midpoint of BCBC, the similarity ratio of BFG\triangle BFG to BAC\triangle BAC is k=12k = \frac{1}{2}. The ratio of their areas is k2=14k^2 = \frac{1}{4}. The area of BFG\triangle BFG is 128×14=32128 \times \frac{1}{4} = 32.
Similar triangles have area ratios equal to the square of their similarity ratio.

Anahtar Kavram

The ratio of the areas of similar triangles is equal to the square of their similarity ratio.

Alternatif Yöntem

Using Menelaus's Theorem on triangle ABDABD and transversal FEGFEG can also establish the midpoint relations directly without using coordinates.
Tahmini Süre:3m 0s
Soru 2511Soru

An aerospace company designs two similar solar panels. The smaller panel is in the shape of a parallelogram and has an area of 8080 square centimeters. If the perimeter of the larger panel is 1.51.5 times the perimeter of the smaller panel, what is the area, in square centimeters, of the larger panel?

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Cevap: 180

Cevap

180
Since the two solar panels are similar, the ratio of their perimeters is equal to their linear scale factor, k=1.5k = 1.5. The ratio of their areas is equal to the square of the linear scale factor, k2=(1.5)2=2.25k^2 = (1.5)^2 = 2.25. Therefore, the area of the larger panel is the product of the smaller panel's area and the area scale factor: 80×2.25=18080 \times 2.25 = 180 square centimeters.

Adım Adım Çözüm

1
Determine the linear scale factor between the two similar solar panels.
The linear scale factor is k=1.5k = 1.5.
For similar figures, the ratio of any corresponding linear measurements (such as perimeters) is equal to the linear scale factor. Here, the perimeter of the larger panel is 1.51.5 times that of the smaller panel.
2
Calculate the area scale factor by squaring the linear scale factor.
The area scale factor is k2=(1.5)2=2.25k^2 = (1.5)^2 = 2.25.
The ratio of the areas of two similar two-dimensional shapes is equal to the square of their linear scale factor.
3
Multiply the area of the smaller solar panel by the area scale factor to find the area of the larger panel.
The area of the larger solar panel is 80×2.25=18080 \times 2.25 = 180 square centimeters.
Multiplying the original area by the area scale factor yields the scaled area of the larger similar figure.

Anahtar Kavram

Area scaling of similar figures
Soru 2512Soru

During boreal forest fires, the combustion of organic matter produces pyrogenic carbon (charcoal), which is highly resistant to microbial decomposition. Some ecologists hypothesized that this carbon represents a long-term sink that helps offset carbon dioxide emissions from the fire. However, researcher Maya Lin and her team demonstrated that pyrogenic carbon particles adsorb dissolved organic compounds from the soil, concentrating easily degradable nutrients. This process stimulates local soil microbe activity, which in turn increases the decomposition rate of nearby unburned soil organic matter. Therefore, while pyrogenic carbon itself remains stable, its presence in the soil may ______

Which choice most logically completes the text?

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Cevap: indirectly accelerate the loss of other carbon pools within the forest ecosystem.

Cevap

The correct answer is the option stating that pyrogenic carbon may indirectly accelerate the loss of other carbon pools within the forest ecosystem.
The correct option is supported because the passage states that pyrogenic carbon stimulates microbial activity, which increases the decomposition rate of nearby unburned soil organic matter. Because this unburned matter contains carbon, accelerating its decomposition leads to a loss of carbon from other pools in the forest ecosystem.

Adım Adım Çözüm

1
Identify the key characteristics of pyrogenic carbon described in the passage.
Pyrogenic carbon is highly stable and resistant to decomposition, but it adsorbs dissolved organic compounds and concentrates nutrients.
Establishing the baseline properties of the carbon helps define what it does directly.
2
Determine the ecological consequence of this nutrient concentration.
The concentrated nutrients stimulate soil microbes, which then decompose nearby unburned organic matter at a higher rate.
This establishes the chain of cause and effect resulting from the presence of pyrogenic carbon.
3
Synthesize these findings to draw a logical conclusion.
Even though pyrogenic carbon is a stable sink, its presence causes the breakdown and loss of other organic matter (another carbon pool) in the soil.
This completes the logical gap in the text by connecting the stable carbon's effect to the loss of surrounding carbon pools.

Anahtar Kavram

Logical Inferences
Soru 2513Soru

An acute angle θ\theta satisfies the equation sin(θ)=0.6\sin(\theta) = 0.6. What is the value of cos(θ)\cos(\theta)?

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Cevap: 0.8

Cevap

The value of cos(θ)\cos(\theta) is 0.8.
Using the fundamental Pythagorean trigonometric identity sin2(θ)+cos2(θ)=1\sin^2(\theta) + \cos^2(\theta) = 1, we substitute the given value sin(θ)=0.6\sin(\theta) = 0.6 to obtain (0.6)2+cos2(θ)=1(0.6)^2 + \cos^2(\theta) = 1, which simplifies to 0.36+cos2(θ)=10.36 + \cos^2(\theta) = 1. Subtracting 0.360.36 from both sides yields cos2(θ)=0.64\cos^2(\theta) = 0.64. Taking the positive square root because θ\theta is an acute angle gives cos(θ)=0.8\cos(\theta) = 0.8.

Adım Adım Çözüm

1
State the Pythagorean trigonometric identity
sin2(θ)+cos2(θ)=1\sin^2(\theta) + \cos^2(\theta) = 1
This identity relates the sine and cosine of any angle.
2
Substitute the value of sin(θ)\sin(\theta) into the identity
(0.6)2+cos2(θ)=1(0.6)^2 + \cos^2(\theta) = 1
We are given that sin(θ)=0.6\sin(\theta) = 0.6.
3
Solve for cos2(θ)\cos^2(\theta)
cos2(θ)=0.64\cos^2(\theta) = 0.64
Subtracting 0.360.36 from 11 isolates the squared cosine term.
4
Take the square root of both sides
cos(θ)=0.8\cos(\theta) = 0.8
Since θ\theta is an acute angle, the value of cos(θ)\cos(\theta) must be positive.

Anahtar Kavram

Pythagorean Identity
Soru 2514Soru

In the study of art history, researchers long believed that the vibrant blue pigment used in ancient Maya murals, known as Maya Blue, was highly susceptible to biodegradation over centuries due to its organic dye component, indigo. ________, recent chemical analysis has revealed that the encapsulation of indigo molecules within the crystalline channels of the clay palygorskite creates a highly stable organo-clay complex that is impervious to acids, alkalis, and microbial attack.

Which choice completes the passage with the most logical transition?

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Cevap: However,

Cevap

However,
The correct answer is the option stating 'However,'. The first sentence outlines a long-held belief that Maya Blue pigment is vulnerable to biodegradation. The second sentence presents recent chemical findings showing that it is actually highly stable and resistant to damage. This transition of ideas is a direct contrast, which is correctly signaled by 'However,'.

Adım Adım Çözüm

1
Analyze the relationship between the two parts of the passage.
The first sentence notes a historical belief that Maya Blue pigment is fragile and susceptible to biodegradation. The second sentence introduces modern scientific evidence showing that the pigment is extremely stable and resistant to decay.
Understanding the logical connection between the ideas is necessary to determine the correct transition.
2
Determine the type of transition required.
Since the passage moves from a belief of susceptibility to a finding of high durability, a contrast or concession transition is needed to connect these opposing ideas.
This establishes the logical relation that the correct transition must signal.
3
Evaluate the choices based on the identified relationship.
The option stating 'However,' is a contrast transition and fits the context. The option stating 'Subsequently,' signals chronology; the option stating 'For instance,' signals exemplification; and the option stating 'Furthermore,' signals addition. None of these other options express contrast.
Only one option correctly aligns with the contrast relationship established in the passage.

Anahtar Kavram

Transitions: Contrast and Concession
Tahmini Süre:1m 15s
Soru 2515Soru

The Antarctic hair grass (*Deschampsia antarctica*) is one of only two flowering plant species native to Antarctica. To survive the region’s extreme cold and high ultraviolet (UV) radiation, the plant produces high concentrations of sucrose and specialized proteins, such as dehydrins. Sucrose acts as a natural cryoprotectant, preventing ice crystal formation within the plant's cells, while dehydrins stabilize cell membranes during sudden freezing events. Researchers have also observed that *D. antarctica* exhibits an unusually high rate of self-pollination, a reproductive strategy that minimizes its reliance on insect pollinators, which are extremely scarce in the harsh Antarctic environment.

Based on the text, what is true of the dehydrins produced by *Deschampsia antarctica*?

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Cevap: They help stabilize the plant's cell membranes during sudden freezing events.

Cevap

They help stabilize the plant's cell membranes during sudden freezing events.
The correct option is supported by the text, which explicitly states that 'dehydrins stabilize cell membranes during sudden freezing events.'

Adım Adım Çözüm

1
Identify the target of the question in the passage.
The question asks about the function or characteristics of dehydrins in *Deschampsia antarctica*.
This focuses the reading on the specific section of the text discussing dehydrins.
2
Locate the explicit detail regarding dehydrins in the passage.
The text states: 'dehydrins stabilize cell membranes during sudden freezing events.'
An explicit details question requires identifying information directly stated in the text.
3
Evaluate the choices to find the one that directly matches the located text.
The option stating that dehydrins help stabilize the plant's cell membranes during sudden freezing events directly matches the explicit detail.
This confirms the correct option while eliminating choices that misread details, speculate, or reference other parts of the text.

Anahtar Kavram

Explicit Details
Soru 2516Soru

A right triangle in the xyxy-plane has vertices at the coordinates (0,0)(0, 0), (15,0)(15, 0), and (15,8)(15, 8). What is the perimeter of this triangle?

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Cevap: 40

Cevap

The perimeter of the triangle is 40.
The perimeter of the triangle is the sum of its three side lengths. The horizontal leg has a length of 1515 (from (0,0)(0,0) to (15,0)(15,0)), and the vertical leg has a length of 88 (from (15,0)(15,0) to (15,8)(15,8)). Using the Pythagorean theorem, the hypotenuse has a length of 152+82=225+64=17\sqrt{15^2 + 8^2} = \sqrt{225 + 64} = 17. Summing these three lengths gives a perimeter of 15+8+17=4015 + 8 + 17 = 40.

Adım Adım Çözüm

1
Identify the lengths of the two perpendicular legs of the right triangle from the given coordinates.
The horizontal leg lies on the x-axis from (0,0)(0, 0) to (15,0)(15, 0), which has a length of 150=1515 - 0 = 15. The vertical leg runs parallel to the y-axis from (15,0)(15, 0) to (15,8)(15, 8), which has a length of 80=88 - 0 = 8.
The length of horizontal and vertical segments in a coordinate plane can be found by taking the absolute difference of their non-matching coordinates.
2
Use the Pythagorean theorem to calculate the length of the hypotenuse.
The hypotenuse length is 152+82=225+64=289=17\sqrt{15^2 + 8^2} = \sqrt{225 + 64} = \sqrt{289} = 17.
The Pythagorean theorem states that a2+b2=c2a^2 + b^2 = c^2 for any right triangle with legs aa and bb and hypotenuse cc.
3
Calculate the perimeter of the triangle by summing the lengths of all three sides.
15+8+17=4015 + 8 + 17 = 40.
The perimeter of a triangle is the total distance around the boundary, which equals the sum of its three side lengths.

Anahtar Kavram

Calculating the perimeter of a right triangle in the coordinate plane by using the Pythagorean theorem to find the hypotenuse.
Soru 2517Soru

In the xyxy-plane, the graph of the quadratic function ff, defined by f(x)=(x4)2+cf(x) = -(x - 4)^2 + c where cc is a constant, intersects the xx-axis at two points. If the distance between these two points is 1010, what is the value of cc?

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Cevap: 25

Cevap

25
The quadratic function is defined by f(x)=(x4)2+cf(x) = -(x - 4)^2 + c, which is in the vertex form f(x)=a(xh)2+kf(x) = a(x - h)^2 + k. The vertex of this parabola is at (4,c)(4, c), and the vertical line x=4x = 4 is its axis of symmetry. The distance between the two xx-intercepts is 1010. By symmetry, the intercepts must be located 55 units to the left and right of the axis of symmetry, placing them at x=45=1x = 4 - 5 = -1 and x=4+5=9x = 4 + 5 = 9. Since the graph intersects the xx-axis at these points, substituting either xx-coordinate into the function gives a yy-value of 00. Substituting x=9x = 9 yields 0=(94)2+c0 = -(9 - 4)^2 + c, which simplifies to 0=25+c0 = -25 + c, so c=25c = 25.

Adım Adım Çözüm

1
Identify the axis of symmetry of the quadratic function.
The axis of symmetry is x=4x = 4.
The function f(x)=(x4)2+cf(x) = -(x - 4)^2 + c is written in vertex form, y=a(xh)2+ky = a(x - h)^2 + k, where the vertex is (h,k)(h, k) and the axis of symmetry is x=hx = h.
2
Find the xx-coordinates of the xx-intercepts using the distance between them.
The xx-intercepts are at x=1x = -1 and x=9x = 9.
Since the parabola is symmetric about the line x=4x = 4 and the distance between the two intercepts is 1010, each intercept is 102=5\frac{10}{2} = 5 units away from the axis of symmetry. Thus, the intercepts are at 45=14 - 5 = -1 and 4+5=94 + 5 = 9.
3
Substitute one of the xx-intercepts into the function to solve for the constant cc.
c=25c = 25
Since (9,0)(9, 0) is on the graph, f(9)=0f(9) = 0. Substituting this gives 0=(94)2+c    0=25+c    c=250 = -(9 - 4)^2 + c \implies 0 = -25 + c \implies c = 25.

Anahtar Kavram

Using symmetry and the vertex form of a quadratic function to determine constants from key graphical features such as xx-intercepts.
Soru 2518Soru

While researching the Cherokee writing system, a student takes the following notes:
* Sequoyah, a Cherokee silversmith, began developing a writing system for the Cherokee language in 1809.
* He completed the system, a syllabary of 85 characters representing spoken syllables, in 1821.
* Prior to Sequoyah's syllabary, the Cherokee language was purely oral.
* Within a decade of its introduction, the system enabled the Cherokee people to achieve literacy rates higher than those of neighboring European-American settlers.

The student wants to summarize the creation and impact of the Cherokee writing system. Which choice most effectively uses information from the given notes to accomplish this goal?

Cevabı ve açıklamayı göster

Cevap: Although the Cherokee language was purely oral prior to 1809, the 85-character syllabary completed by Sequoyah in 1821 was rapidly adopted, enabling Cherokee literacy rates to surpass those of neighboring settlers within a decade.

Cevap

Although the Cherokee language was purely oral prior to 1809, the 85-character syllabary completed by Sequoyah in 1821 was rapidly adopted, enabling Cherokee literacy rates to surpass those of neighboring settlers within a decade.
The correct choice summarizes both the creation and the impact of the writing system by noting that the 85-character syllabary was completed by Sequoyah in 1821 (creation) and that it led to literacy rates that surpassed those of neighboring settlers within a decade (impact).

Adım Adım Çözüm

1
Analyze the rhetorical goal of the prompt.
The student wants to summarize both the creation and the impact of the Cherokee writing system.
This establishes the criteria that the correct choice must meet.
2
Evaluate the choices against the notes to find which one includes both aspects.
The option stating that Sequoyah completed the syllabary in 1821 and that it enabled Cherokee literacy rates to surpass those of neighboring settlers includes both the creation and the impact.
It addresses all components of the rhetorical goal.
3
Verify that the selected choice is factually accurate based on the notes.
The details (oral history, 85-character syllabary, Sequoyah, 1821 completion, and literacy rates surpassing neighboring settlers) match the notes perfectly.
This ensures the choice does not introduce misread details or external facts.

Anahtar Kavram

Summarizing notes to meet a specific rhetorical goal.
Tahmini Süre:1m 30s
Soru 2519Soru

While preparing a presentation on branches of zoology, a student took the following notes:
* Myrmecology is the branch of entomology focused on the scientific study of ants.
* The name of the field is derived from the Greek words *myrmex* (meaning "ant") and *logos* (meaning "study").
* Myrmecologists research diverse topics, including ant social structures, chemical communication, and ecological roles.
* Key foundational research in the discipline was conducted in the early twentieth century by entomologist William Morton Wheeler.

The student wants to introduce myrmecology to an audience unfamiliar with the field. Which choice most effectively uses information from the given notes to accomplish this goal?

Cevabı ve açıklamayı göster

Cevap: Derived from the Greek words for "ant" and "study," myrmecology is the branch of entomology focused on the scientific study of ants.

Cevap

The choice that states that myrmecology is the branch of entomology focused on the scientific study of ants, deriving its name from the Greek words for "ant" and "study," is the correct answer.
The correct option effectively introduces the field of myrmecology by defining it as the branch of entomology focused on the scientific study of ants, and explaining the origin of its name. This combination of definition and etymology is the most direct way to introduce the subject to an audience that is unfamiliar with it.

Adım Adım Çözüm

1
Analyze the student's goal.
The goal is to introduce the field of myrmecology to an unfamiliar audience.
This requires selecting an option that clearly defines the term and explains the core focus of the field.
2
Evaluate the notes for relevant details.
The first note defines myrmecology as the branch of entomology focused on the scientific study of ants. The second note provides the etymology (Greek words for "ant" and "study"). These two details combined provide a clear introduction.
An introduction of a scientific discipline typically involves its definition and basic scope.
3
Evaluate the answer choices against the goal.
The option defining myrmecology using its Greek roots and identifying it as the branch of entomology studying ants successfully accomplishes the goal. The other options focus on historical figures or specific research topics rather than defining/introducing the field.
Only one option synthesizes the definition and etymology to introduce the subject to a new audience.

Anahtar Kavram

Rhetorical Synthesis: Introduction and Definition
Soru 2520Soru

Many cognitive scientists hypothesized that language acquisition in infants relies entirely on domain-general learning mechanisms, such as pattern recognition and statistical learning. A recent study by Dr. Clara Mendez showed that infants are highly sensitive to statistical regularities in speech. ________, Mendez's team observed that this sensitivity alone is insufficient for infants to grasp syntactic structure, which appears to require innate domain-specific constraints.

Which choice completes the passage with the most logical transition?

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Cevap: Nevertheless

Cevap

The transition 'Nevertheless' is the most logical choice because it establishes a contrast or concession, indicating that despite the evidence of infants' statistical sensitivity, this sensitivity remains insufficient for acquiring syntax.
The transition 'Nevertheless' is correct because it properly establishes a contrast/concession relationship. The preceding sentence highlights a positive finding (infants' high sensitivity to statistical regularities), while the subsequent sentence introduces a critical limitation (this sensitivity is insufficient on its own for syntax acquisition). 'Nevertheless' correctly signals this concession.

Adım Adım Çözüm

1
Identify the relationship between the ideas in the sentences surrounding the blank.
The sentence before the blank describes a finding that infants are highly sensitive to statistical patterns. The sentence after the blank points out that this sensitivity is not enough for infants to acquire grammar.
Understanding the logical connection between the statements is necessary to choose the correct transition.
2
Determine the type of transition required to connect these ideas.
A transition indicating contrast or concession is needed because the second statement introduces a limitation that qualifies the positive finding of the first statement.
This guides the selection of the transition word that matches the logical direction of the text.
3
Evaluate the choices to find the one that fits the contrast/concession relationship.
'Nevertheless' is the only transition among the choices that expresses contrast or concession.
Selecting the correct transition ensures the passage flows logically and coherent meaning is maintained.

Anahtar Kavram

Transitions: Contrast and Concession
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