采煤机检修后空转试运转,首先应该合上截割部()手把。
A.开关
B.操作
C.启动
D.离合器
参考答案:D
(2014·江西南昌两校第四次联考)—Don’t worry.I had a license years ago.I’m not green.
—________!I’ll tell my daughter that everything is OK on the way.
A.What a relief
B.Congratulations
C.How surprising
D.I’m so sorry
TCP/IP参考模型分成( )层。
A.2
B.3
C.4
D.5