所有的机电设备在使用过程中不可避免地要发生磨损，简述磨损有哪些内容？

运行管理

A.had not been, would have had

B.was not, would have had

c.had not been, would have

D.were not, would have had

A．1

B．2

C．6

D．8

All experts agree that the most important consideration with diet drugs is carefully ____ the risks and benefits.

A.valuing

B.evaluating

C.weighing

D.supposing

简述羊水栓塞的临床表现和处理原则。

酵母菌无氧呼吸不能产生的物质是

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A．CO2 B．丙酮酸 C．乳酸 D．酒精