单项选择题
The bearings used to support the crankshaft are generally called （）
A.line shaft bearings B.connecting rod beatings C.main bearings D.support bearings
单项选择题 Improper maintenance of an automatic auxiliary boiler oil burner could result in （）.
单项选择题 The highest pressure in any closed diesel engine freshwater cooling system is at the （）.
单项选择题 The lube oil cooler is located after the lube oil filter in order for （）
