Tüm alıştırma soruları

In 1915, chemist Alice Ball developed an injectable form of oil derived from seeds of the *Hydnocarpus* tree, providing the first effective treatment for Hansen's disease (leprosy). Prior to Ball’s innovation, patients were treated with raw chaulmoogra oil, which was too viscous for intravenous administration and produced unbearable digestive distress when ingested orally. Ball solved this problem by isolating the active ethyl esters of the chaulmoogra fatty acids, rendering the compound water-soluble and capable of absorption into the bloodstream without causing severe localized tissue necrosis. Although her supervisor, Arthur L. Dean, published the method following Ball's death in 1916 without granting her co-authorship, local physician Harry T. Hollmann publicly documented Ball's priority in 1922, designating the technique the "Ball Method."

According to the passage, prior to the development of the "Ball Method," treatment of Hansen's disease with chaulmoogra oil presented which of the following complications?

Select all choices that apply.

If $x$ satisfies the linear equation $\frac{3(x - 1)}{2} - \frac{x + 5}{4} = \frac{2x - 3}{3}$, what is the value of $4x + 7$?

When the expression $\frac{3x^2 - 12}{x - 2}$ is completely simplified, it can be written in the form $ax + b$ for all $x \neq 2$, where $a$ and $b$ are constants. What is the value of $a + b$?

Which words best complete the passage so that the text maintains logical coherence and proper inter-blank structural dependency?

If $x$ and $y$ are real numbers such that $-1 < x < 0 < y < 1$, which of the following statements MUST be true? Select all such statements.

At a clothing retailer, the wholesale cost of a leather coat was $50\%$ greater than the wholesale cost of a denim jacket. The following year, the wholesale cost of the leather coat increased by $20\%$, while the wholesale cost of the denim jacket decreased by $10\%$. What was the overall percentage increase in the combined wholesale cost of one leather coat and one denim jacket?

Read the passage below:

For decades, nineteenth-century astrophysicists regarded solar spectrographic lines as purely (i)________ anomalies, treating each spectral line as an isolated curiosity rather than an index of atomic architecture. However, once laboratory experimenters demonstrated that atomic emissions follow predictable mathematical series, this assumption was entirely (ii)________. Far from being meaningless noise, spectral lines were recognized as (iii)________ indicators of atomic energy transitions, effectively laying the groundwork for quantum mechanics.

Which set of terms, when inserted into the blanks in order, best maintains the cross-sentence contextual coherence of the passage?

In Month 1, a data center's two facilities, Facility A and Facility B, consumed a combined total of $120,000\text{ kWh}$ of electricity. In Month 2, Facility A decreased its electricity consumption by $15\%$, while Facility B increased its electricity consumption by $20\%$. If the combined electricity consumption of the two facilities increased by $6\%$ overall in Month 2, how many kilowatt-hours ($\text{kWh}$) of electricity did Facility A consume in Month 1?

An automated micro-dispenser delivers liquid reagents in precise doses. Each dose has a volume of $3.6 \times 10^{-5}$ liters. If a reservoir containing $0.0162$ liters of reagent is emptied completely by delivering these equal doses, how many doses were delivered?

Line $L$ is defined by the equation $3x - 4y = 12$. Line $M$ is perpendicular to line $L$ and passes through the point $(6, -1)$. Which of the following statements about line $M$ must be true? Select all that apply.

If $x$ is a positive real number such that $2x^2 - 5x - 3 = 0$, what is the value of $x^2 + 1$?

Passage:
In 1891, German amateur scientist Agnes Pockels published a landmark paper detailing her development of a rectangular slide trough designed to measure the surface tension of water. Operating without access to a formal laboratory, Pockels devised a mechanism featuring a movable strip of tin that traversed the surface of a water-filled tray, allowing her to systematically manipulate surface impurities. By measuring the force required to detach a small ring from the liquid surface at varying concentrations of oil, she demonstrated that surface tension remains largely constant until oil molecules form a contiguous monomolecular layer, after which tension drops precipitously. Lord Rayleigh, to whom Pockels had originally sent her observations in a letter written in German, facilitated the paper's publication after recognizing that her device provided a far more precise quantitative measurement of monolayer coverage than previous methods, which relied on static liquid drops.

According to the passage, Pockels evaluated the behavior of surface tension across different oil concentrations by measuring which of the following?

The mass of a sample in a laboratory experiment is given by the expression $M = 0.000375 \times 10^n$ grams, where $n$ is an integer. When $M$ is written in standard scientific notation as $a \times 10^k$, where $1 \le a < 10$ and $k$ is an integer, the exponent $k$ is equal to $-2$. What is the value of $n$?

In the $xy$-plane, line $k$ passes through the point $(2, -3)$ and has a slope of $-\frac{4}{3}$. Line $m$ is parallel to line $k$ and has an $x$-intercept at $(6, 0)$. What is the $y$-intercept of line $m$?

Complete the passage below by filling in the blank with the word that best fits the context based on structural clues and transition signals.

In geomorphology, the evolution of bedrock rivers is often governed by knickpoints—abrupt slope alterations in a river profile usually caused by tectonic uplift or base-level lowering. While early models treated knickpoints as static boundaries marking distinct erosional regimes, recent hydrodynamic simulations demonstrate that knickpoints actively propagate upstream, consuming the relict landscape above them. As the slope steepens, the resulting increase in shear stress enhances bedrock incision, driving a continuous wave of retreat. Far from merely transmitting a passive signal of environmental perturbation, this migratory behavior reflects a dynamic readjustment of channel geometry. Consequently, geomorphologists must view knickpoint migration not as an ephemeral anomaly, but as the primary mechanism through which drainage basins continuously sculpt landscape topographies over geological timescales.

Based on the passage above, which of the following best captures the meaning of the word propagate as it is used by the author?

A regional library recorded the daily number of public computer reservations over a 7-day period: $14, 25, 18, 31, 25, 12,$ and $21$. During the following week, 2 additional daily reservation values, $x$ and $y$, were added to the dataset. If the median of the resulting 9-day dataset is equal to the mode of the original 7-day dataset, which of the following values could be the sum of $x$ and $y$?

A specialty coffee shop prepares two custom coffee bean blends using Arabica and Robusta beans. The first 10-pound blend consists of 4 pounds of Arabica beans and 6 pounds of Robusta beans and costs $\$52$. The second 10-pound blend consists of 7 pounds of Arabica beans and 3 pounds of Robusta beans and costs $\$61$. What is the cost, in dollars, of 1 pound of Arabica coffee beans?