An exhaust fan is rated 110 cfm. How much air does it move in 18 minutes?
Correct Answer
A) 1,980 cubic feet.
At 110 cubic feet per minute for 18 minutes, the fan moves 1,980 cubic feet.
Why This Is the Correct Answer
At 110 cubic feet per minute for 18 minutes, the fan moves 1,980 cubic feet.
Why the Other Options Are Wrong
Option B: 1,760 cubic feet total.
1,760 cubic feet total. is below the supported result for mechanical airflow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 2,080 cubic feet total.
2,080 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: 2,420 cubic feet total.
2,420 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.
Memory Technique
Mechanical Airflow cart for Checking Ventilation: controlling first, minute 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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