One of the reasons that causes oil flowed from sludge outlet of a self-cleaning purifier is

A．seal water supply be cut off

B．make-up water supply be cut off

C．oil outlet valve closed or not open sufficiently

D．the flow rate of oil is too much

[主观题]What causes the lube oil pressure of the engine to drop ?

[单选题]One of the most common causes of reduction gear failure is gear wear caused by scoring as a result ofA．surface fatigue of the gearsB．an inadequate lube oil filmC．plastic flow of the gearsD．fretting corrosion from water

[单选题]In discussing oil pollution, one important fact to remember is that the problem remains the same( )heavy( )light oil is spilled into the water.A．both/andB．whether/orC．neither/norD．because/so

[单选题]Fuel oil is thought to be one of the main factors （） the operation and maintenance of an engine.A . have nothing to do withB . having nothing to do withC . have much to do withD . having much to do with

“One of the main reasons for economic failure in many African countries is the f

Knowing these causes can make us examine our behavior， and correct bad habits. T

They have not had a strict system of landownership, one of the universal causes

[单选题]One of the main reasons for getting students to listen to spoken English is

[单选题]One of the reasons for high-school graduates not taking a gap year is that_

Here is one of the obvious reasons why you should still bother to get business c