单选题Medium speed engines have a （） power to weight ratio than the slow speed two strokes, but due to the higher speeds tend to have （） maintenance intervals.Ahigher；reducedBhigher；increasedClower；reducedDlower；increased
单选题
Medium speed engines have a （） power to weight ratio than the slow speed two strokes, but due to the higher speeds tend to have （） maintenance intervals.
A
higher；reduced
B
higher；increased
C
lower；reduced
D
lower；increased
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