Drill 28 · Reading & Writing · Hard Command of Evidence
SAT R&W Command of Evidence (Hard) — Drill 28 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.
How long a sheet of paper lasts, and why one batch browns while another stays white, runs through this set. Each finding hands you a result about aging or fiber and asks which observation settles a dispute about its cause. The two data items, a table and a bar comparison, reward reading for the gap between two conditions rather than for one bar alone. The quotation item draws from a nineteenth-century book about a river.
Many books printed in the later nineteenth century brown and grow brittle far faster than books from a century earlier. One explanation blames the acidic sizing added to the later paper during manufacture, which slowly attacks the fibers. Another blames the switch to a different raw fiber used in the later sheets, which may simply be less stable. A conservator wants evidence that points to the sizing rather than the fiber, and examines sheets from the period that vary in one respect while matching in the other.
Question 1. Which finding, if true, would most strongly support the acidic-sizing explanation over the fiber-source explanation?
Explanation: Correct: Holding the fiber constant and varying only the sizing isolates the cause: same later fiber stays sound when unsized but browns once the acidic sizing is added. That points the finger at the sizing, not the fiber. A: Larger press runs speak to how many copies were made, not to why the paper itself decays; it bears on neither the sizing nor the fiber as a cause. B: Edge-first browning shows air exposure matters, which would happen under either cause; it does not point to the sizing over the fiber. C: Pages browning under light-blocking covers argues against light as the driver, but says nothing about sizing versus fiber as the cause.
Table: four archived paper samples
An archive rates four paper samples for long-term survival using two conditions together: the paper must be low in acid (a pH at or above 6.5) and it must have been kept in cool storage (at or below 16 °C). A sample that meets only one condition is judged at risk. The table lists each sample's measured pH and its long-term storage temperature.
Question 2. Based on the table, which sample meets both of the archive's conditions for long-term survival?
Explanation: Correct: Sample 2 is the only one that meets both thresholds: its pH is 7.1 (at or above 6.5) and its storage temperature is 14 degrees Celsius (at or below 16). Both conditions are met at once. A: Sample 1 was kept cool at 12 degrees Celsius but its pH is 5.4, well below the 6.5 acidity limit, so it fails the low-acid condition. C: Sample 3 has a high enough pH at 7.4 but was stored warm at 21 degrees Celsius, above the 16-degree limit, so it fails the cool-storage condition. D: Sample 4 misses on both counts -- pH 6.0 and storage at 19 degrees Celsius -- so it is not the sample that satisfies both.
A conservator plans to slow the decay of a stack of acidic letters by misting each sheet with a mild alkaline spray that neutralizes acid on contact. The plan assumes the treatment will protect the whole sheet, not just its surface. For that to hold, the spray has to reach the acid held deep inside the paper, not merely coat the outermost layer of fibers.
Question 3. Which finding, if true, would most undermine the conservator's assumption that the spray will protect the whole sheet?
Explanation: Correct: The plan depends on the spray reaching acid throughout the sheet. If the droplets bead up and dry on the surface without soaking in, the interior acid is never touched, so the assumption that the whole sheet is protected fails. A: Fast neutralization on contact supports the plan; it does not threaten the assumption that the spray reaches the interior. B: Acidic ink names another acid source but does not bear on whether the spray can penetrate the sheet to do its job. D: Equal dampness afterward is about moisture left behind, not about whether the treatment soaked in deeply enough to reach interior acid.
A student reads the opening chapter of a nineteenth-century book in which the author sets out to show how extraordinary the Mississippi River is. The student argues that one sentence backs the river's claim to remarkableness specifically by the sheer volume of water it carries compared with other great rivers.
Question 4. Which quotation most directly supports the student's claim about the river's remarkableness resting on the volume of water it carries?
Explanation: Correct: The claim is specifically about volume of water carried. The keyed line measures the river by exactly that -- its discharge set against the St. Lawrence, the Rhine, and the Thames -- which is the volume comparison the student points to. A: This asserts the river is remarkable but names no measure at all, let alone volume of water; it states the claim's conclusion without the water-volume support. B: Length is a different measure of remarkableness; the longest-river line is about distance, not the volume of water carried. C: Crookedness is yet another measure -- the river's winding path -- and says nothing about how much water it discharges.
A lab tests whether an added alkaline buffer protects paper from yellowing when the air turns humid. Two paper types, one buffered and one unbuffered, are each measured for yellowing after dry storage and again after humid storage. The bar chart shows all four values. A reviewer notes that the buffered paper yellowing less in any single condition would not settle the question; what matters is which paper's yellowing climbs less when the air goes from dry to humid.
Question 5. Which statement best compares how much the move from dry to humid air raises yellowing in the two papers?
Explanation: Correct: From dry to humid the unbuffered paper jumps from 8 to 30 (a rise of 22) while the buffered paper edges from 6 to 12 (a rise of 6). The humidity penalty is far larger for the unbuffered paper, which is the comparison the question is built around. B: More humid-storage yellowing in the unbuffered paper (30 versus 12) is true but compares a single condition; it does not capture how much each paper changed from dry to humid. C: Some dry-storage yellowing in the buffered paper (6) is a single value and says nothing about the dry-to-humid increase the question targets. D: Both papers do yellow more when humid, but sharing that direction does not show whose yellowing rises more steeply.