A sump pump discharges 18 gallons per minute for 42 minutes. How many gallons are pumped?
Correct Answer
A) 756 gallons.
Volume equals flow rate times time, so 18 gallons per minute for 42 minutes equals 756 gallons.
Why This Is the Correct Answer
Volume equals flow rate times time, so 18 gallons per minute for 42 minutes equals 756 gallons.
Why the Other Options Are Wrong
Option B: 720 gallons total.
720 gallons total. is below the supported result for plumbing flow calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 786 gallons total.
786 gallons total. is above the supported result for plumbing flow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 840 gallons total.
840 gallons total. is above the supported result for plumbing flow calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Plumbing Flow cart for Estimating Temporary: volume first, rate second, whole the controlling choice last.
Reference Hint
Study anchor (closed-book): memorize Plumbing flow calculation from California Plumbing Code, California Code of Regulations Title 24. / Title 24 California Plumbing Code pump capacity concepts; know the rule or calculation trigger without relying on exam-room lookup.
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