Question 176·Hard·Rhetorical Synthesis
While researching a topic, a student has taken the following notes:
- Environmental engineer Lara Nguyen investigated the impact of installing "cool roofs"—white, highly reflective rooftop coatings—on summertime urban heat.
- She collected surface-temperature data from twenty adjacent city blocks for three weeks before and three weeks after the coatings were applied.
- Results showed an average midday surface-temperature decrease of 5 °C on coated roofs.
- Buildings with coated roofs used 18 percent less electricity for air-conditioning during the study period.
- Blocks with mature tree canopies experienced an additional 1 °C cooling unrelated to the roofing material.
The student wants to draft a sentence that accurately summarizes Nguyen’s key finding. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For “notes to summary” questions, first decide whether the task is to describe methods, findings, or both—the wording (“key finding” here) usually tells you. Then scan the notes to identify the main result and any critical numbers. Eliminate options that only talk about setup or background, that overemphasize side details, or that ignore the central quantitative findings. Choose the sentence that is accurate, concise, and focused on the primary outcome the notes highlight.
Hints
Focus on result, not process
Look for the choice that tells you what Nguyen discovered, not just what she measured or how long the study lasted.
Find the central outcome in the notes
Which notes describe the main changes observed after installing cool roofs (think in terms of temperature and electricity use)?
Watch out for side details
One note mentions tree canopies causing additional cooling. Ask yourself: is this the central focus of the study or an extra detail?
Look for specific, quantitative results
Which option includes the important numbers from the notes that best capture the impact of cool roofs?
Step-by-step Explanation
Understand what the question is asking
The prompt says the student wants a sentence that accurately summarizes Nguyen’s key finding.
So the right answer should:
- Focus on results, not just what she did.
- Capture the main outcome of the study from the notes.
Identify the key finding in the notes
Look back at the notes and separate methods from results.
Methods (what she did):
- Investigated cool roofs.
- Collected data from twenty adjacent city blocks.
- Measured for three weeks before and three weeks after.
Results (what she found):
- Average midday surface-temperature decreased by 5 °C on coated roofs.
- Buildings with coated roofs used 18 percent less electricity for air-conditioning.
- Tree canopies gave an additional 1 °C cooling, unrelated to roofing material (a side detail).
The key finding about the cool roofs is the combination of the 5 °C temperature drop and the 18 percent reduction in electricity use.
Eliminate choices that focus on method or side details
Now check each option against that key result:
- One choice mainly describes how the study was done (time frame, accounting for tree canopies) but gives no results.
- Another choice talks generally about both tree canopies and reflective roofs influencing heat, but does not give the main numerical findings and shifts focus away from cool roofs.
- A third choice only mentions installing coatings and tracking temperatures, again focusing on purpose and method, not on what was discovered.
All of these are missing the clear statement of the 5 °C cooling and 18 percent energy reduction that define the key finding.
Match the choice that states the main quantitative results
The remaining option clearly and directly states Nguyen’s key finding by:
- Indicating the data source (twenty city blocks), and
- Reporting both major results: that cool roofs lowered midday roof temperatures by 5 °C and cut air-conditioning electricity use by 18 percent.
Therefore, the correct answer is:
C) Using data from twenty city blocks, environmental engineer Lara Nguyen found that applying highly reflective “cool roofs” lowered midday roof temperatures by 5 °C and cut building air-conditioning electricity use by 18 percent.