An exhaust fan moves 95 cubic feet per minute for 24 minutes. How much air is moved?
Correct Answer
A) 2,280 cubic feet.
Air volume equals airflow times time: 95 cfm for 24 minutes equals 2,280 cubic feet.
Why This Is the Correct Answer
Air volume equals airflow times time: 95 cfm for 24 minutes equals 2,280 cubic feet.
Why the Other Options Are Wrong
Option B: 1,980 cubic feet total.
1,980 cubic feet total. is below the supported result for mechanical airflow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 2,380 cubic feet total.
2,380 cubic feet total. is above the supported result for mechanical airflow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 2,520 cubic feet total.
2,520 cubic feet total. is above the supported result for mechanical airflow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Mechanical Airflow cart for Checking Ventilation: air first, volume second, whole feet last.
Reference Hint
Study anchor (closed-book): memorize Mechanical airflow calculation from California Mechanical Code, California Code of Regulations Title 24. / Title 24 California Mechanical Code exhaust airflow concepts; know the rule or calculation trigger without relying on exam-room lookup.
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