A lawn mower has a 6-horsepower engine (1 HP = 750 W). If the engine has an efficiency of 20%, and the throttle is such that the engine cycles 10 times a second, the heat that is expelled in one cycle is
A. 1 800 J
B. 2 000 J
C. 2 200 J
D. 2 400 J
E. 2 250 J
Answer: A
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