Drill 17 · Reading & Writing · Hard Command of Evidence
SAT Reading & Writing: Hard Command of Evidence (Drill 17) is a Reading & Writing practice drill covering Hard Command of Evidence. It contains 5 original questions created by Brian Stewart, a Barron's test prep author with over 20 years of tutoring experience.
A set of five hard Command of Evidence items spanning new findings, two data displays, and a passage from a classic novel. The traps here mostly tell the truth, but only part of it, or they match the topic while missing the relationship the claim turns on. Pin down what the evidence has to establish, then pick the option that establishes the whole of it.
A river scientist measured how fast the banks wore back at two bends of a channel, a gently curving bend and a sharply curving one, as the flow speed rose. The scientist concluded that the sharp bend is far more sensitive to faster flow, reasoning that water forced around a tight curve presses harder on the outer bank as it speeds up than water rounding a gentle curve.
Question 1. Which choice best describes data from the graph that support the scientist's conclusion?
Explanation: Choice D is the best answer because the conclusion is that the tight bend responds far more to faster flow, which is a claim about the two slopes from a shared start. The graph shows both bends near two centimeters per year at the lowest flow, after which the tight bend rises steeply toward fifty-one while the gentle bend creeps to about twelve, exactly the sharper sensitivity claimed. Choice A is wrong because the tight bend's highest erosion rate is a single endpoint and does not compare how the two bends respond as flow rises. Choice B is wrong because the near-equal rate at the lowest flow is the shared baseline that makes the comparison fair, but on its own it shows no difference in sensitivity. Choice C is wrong because the gentle bend staying below twelve describes only one bend and never contrasts its climb with the tight bend's.
Some ancient glass vessels survive in remarkably clear condition while others of the same age have crusted and decayed. A conservator proposed that the well-preserved vessels owe their durability to a particular mineral additive in their recipe, which makes the glass resist attack by water. The proposal is that the additive, not luck of burial, accounts for the difference.
Question 2. Which finding, if true, would most support the conservator's proposal?
Explanation: Choice A is the best answer because the proposal credits a mineral additive for the durability, so the deciding evidence links the additive to which vessels survived. Finding the additive in the well-preserved vessels and absent from the decayed ones of the same age ties survival to the recipe rather than to chance, just as the conservator claims. Choice B is wrong because finer shaping and decoration describe craftsmanship, not the chemical resistance the proposal is about. Choice C is wrong because that glassmakers tried many recipes is general background and does not connect the additive to the vessels that lasted. Choice D is wrong because better preservation tracking dry, protected burial sites points to burial conditions as the cause, which is the rival the conservator is trying to rule out rather than evidence for the additive.
The House of Mirth (1905) is Edith Wharton's novel of New York society. In an opening scene, Lawrence Selden catches sight of Lily Bart in a crowded station. A student notes that, although Selden has known Lily for years and there is nothing new about her, he finds her endlessly intriguing, as if even her simplest behavior pointed toward some larger purpose.
Question 3. Which quotation from "The House of Mirth" most effectively illustrates the student's claim?
Explanation: Choice C is the best answer because the claim is that Selden finds Lily endlessly intriguing, her plainest acts seeming to serve some larger design. The keyed sentence states exactly that, noting that nothing about her is new yet she always rouses his interest and speculation, her simplest acts seeming the result of far-reaching intentions. Choice A is wrong because the line about the September Monday sets the scene and his errand rather than describing how Lily strikes him. Choice B is wrong because passers-by pausing to look at Lily shows the impression she makes on strangers in the moment, not Selden's lasting sense that her simplest acts hint at some larger design. Choice D is wrong because his impulse to stroll past her reports an action he takes, not the impression that her simplest acts hint at far-reaching intentions.
A field that had been planted with deep-rooted cover crops developed a more crumbly, well-structured soil over a few seasons. An agronomist proposed that earthworms, which multiplied under the cover crops, were the main cause of the improved structure, churning and binding the soil as they burrowed. The reasoning was that worm activity, more than the roots themselves, rebuilt the soil.
Question 4. Which finding, if true, would most directly weaken the agronomist's proposal?
Explanation: Choice B is the best answer because the proposal credits the earthworms for the better structure, so a comparable field that grew the same roots but had almost no worms and still turned crumbly shows the worms were not needed for the improvement. The roots alone producing the same result undercuts the claim that worm activity was the main cause. Choice A is wrong because worms improving soil in general fits the proposal rather than testing whether they, and not the roots, did so here. Choice C is wrong because the cover crops suppressing weeds concerns weed control, a different matter from the crumbly soil structure the proposal tries to explain. Choice D is wrong because worm numbers rising alongside the improvement is the very correlation the proposal rests on, so it supports rather than weakens it.
Decipherment Progress on Four Ancient Scripts
| Script | Distinct signs in the script | Signs now deciphered |
|---|---|---|
| Script J | 80 | 40 |
| Script K | 400 | 120 |
| Script L | 60 | 48 |
| Script M | 250 | 100 |
A scholar wanted to flag the script whose decipherment is furthest along, meaning the one with the largest share of its own signs deciphered, not merely the largest count of deciphered signs. Because the scripts differ in how many signs they contain, the scholar warned that the script with the most signs deciphered need not be the one closest to complete.
Question 5. Which choice most effectively uses data from the table to identify the script the scholar should flag?
Explanation: Choice C is the best answer because the script furthest along is the one with the greatest share of its own signs deciphered, so each deciphered count must be measured against that script's total. Those shares are one half for Script J, three-tenths for Script K, four-fifths for Script L, and two-fifths for Script M, so Script L, with forty-eight of sixty, is furthest along even though its raw count is not the largest. Choice A is wrong because Script K does have the most deciphered signs, but against its four hundred total that is under a third, so the largest count is not the largest share. Choice B is wrong because Script M's one hundred deciphered signs do exceed the smaller scripts' counts, yet against its two hundred fifty total that is two-fifths, below Script L's share. Choice D is wrong because Script J at forty of eighty is exactly half deciphered, a true reading from the table, but a half is short of Script L's four-fifths, so it is not the furthest along.