单项选择题
The lube oil pump used in a diesel engine is a ().
A.volute pump B.centrifugal pump C.diaphragm pump D.gear pump
单项选择题 Most fuel injection nozzles are opened by ().
单项选择题 The total starting air capacity required for reversible main engines is to be sufficient for at least ().
单项选择题 A large, low-speed, main propulsion diesel engine uses sea water to directly cool the ().