A ventilation fan moves 75 cubic feet per minute for 44 minutes. How much air is moved?
Correct Answer
A) 3,300 cubic feet.
Air volume equals airflow times time: 75 cfm for 44 minutes equals 3,300 cubic feet.
Why This Is the Correct Answer
Air volume equals airflow times time: 75 cfm for 44 minutes equals 3,300 cubic feet.
Why the Other Options Are Wrong
Option B: 3,000 cubic feet total.
3,000 cubic feet total. is below the supported result for mechanical airflow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 3,420 cubic feet total.
3,420 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: 3,750 cubic feet total.
3,750 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
Measure to air, adjust for volume, then let Checking Exhaust set the finish line.
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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