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單項(xiàng)選擇題

Proper lubrication of the main bearing is more easily obtained in a single acting four-stroke/cycle diesel engine than in a single acting two-stroke/cycle diesel engine because ()

A.bearing pressure in a four-stroke\cycle acting single diesel engine is continually reversed
B.bearing pressure in a two-stroke\cycle single acting diesel engine is continually reversed
C.the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engine
D.two-stoke/cycle diesel engines require more complicated lubrication piping

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