Before starting an engine by air the engine must .A.be turned by a turning gear for at le

职业资格 已帮助 人

Before starting an engine by air, the engine must .

A.be turned by a turning gear for at least one minute

B.be turned by a turning gear for at least two minutes

C.be turned at least one complete turn

D.be turned at least two complete turns

请帮忙给出正确答案和分析,谢谢!

热搜:n维列向量组a1,an-1线性无关,且与非零向量正交