The fan runtime plan uses a fan moving 110 cubic feet per minute for 28 minutes. How many cubic feet of air are moved?
Correct Answer
A) 3,080 cubic feet.
Air volume equals airflow times time: 110 cfm for 28 minutes equals 3,080 cubic feet.
Why This Is the Correct Answer
Air volume equals airflow times time: 110 cfm for 28 minutes equals 3,080 cubic feet.
Why the Other Options Are Wrong
Option B: 2,940 cubic feet total.
2,940 cubic feet total. is below the supported result for mechanical airflow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 3,220 cubic feet total.
3,220 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: 3,520 cubic feet total.
3,520 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
Checking Exhaust takeoff: count the condition before counting the package.
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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