单项选择题
A.higher torque but lower brake horsepower
B.lower torque but higher brake horsepower
C.higher torque and lower brake horsepower
D.lower torque and higher brake horsepower
单项选择题 Lubricating oil used in a diesel engine serves to（）
单项选择题 Which of the terms listed below represents the operational speed at which excessive engine vibration is created?（）
单项选择题 A dirty fuel oil filter is can be detected by （） Ⅰ.fuel oil analysis Ⅱ.observing the pressure drop across the filter