Question 139·200 Super-Hard SAT Reading Questions·Expression of Ideas
While researching a topic, a student has taken the following notes:
- Many ancient Roman sea walls remain structurally sound after more than 1,800 years.
- The mechanism behind this durability has been debated.
- Materials scientist Admir Lazic proposed that 'hot mixing' with quicklime produced lime clasts that later help self-heal cracks.
- The team examined Roman samples using scanning electron microscopy and chemical mapping to identify lime clasts.
- They produced modern concrete with and without hot mixing.
- The researchers intentionally cracked these samples and ran water through to observe sealing behavior; hot-mixed specimens sealed in less than two weeks.
The student wants to explain the researchers’ hypothesis and the experimental approach used to test it. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For note-synthesis questions, identify exactly what the question demands (here: hypothesis + experimental approach). Then match each demand to specific bullets in the notes and choose the option that includes all required elements while staying strictly faithful to the notes—reject choices that subtly swap causes, change what was tested/measured, or add conclusions not stated.
Hints
Locate the hypothesis
Find the note that says what Lazic proposed caused the durability (it mentions hot mixing, quicklime, and lime clasts).
List the methods
Identify the notes describing what the researchers did: (1) how they examined Roman samples and (2) how they tested modern samples.
Eliminate subtle inaccuracies
Wrong choices often keep the structure (hypothesis + method) but swap a cause, change what was measured, or reverse which sample type sealed quickly.
Step-by-step Explanation
Clarify the required components
The question asks for a sentence that explains both (1) the researchers’ hypothesis and (2) the experimental approach used to test it. A correct choice must include the proposed mechanism and the key methods used to evaluate it.
Extract the hypothesis from the notes
The notes state that Admir Lazic proposed that “hot mixing” with quicklime produced lime clasts that later help self-heal cracks. Any correct choice must include hot mixing, quicklime, lime clasts, and the self-healing idea.
Extract the experimental approach from the notes
The testing approach in the notes has two main parts:
- Analyze Roman samples using scanning electron microscopy and chemical mapping to identify lime clasts.
- Make modern concrete with and without hot mixing, intentionally crack the samples, and run water through them to compare sealing behavior (a crack-and-flow comparison).
Select the choice that matches both parts accurately
Only this option correctly includes the hypothesis and both parts of the testing approach without adding or altering details:
Admir Lazic hypothesized that hot mixing with quicklime produced lime clasts that later self-heal cracks; his team identified clasts in Roman samples using microscopy and chemical mapping and then compared cracked modern concretes made with and without hot mixing by flowing water through them.