无动力装置的止回阀是为了防止列车管减压时,()的压力空气向列车管逆流
A、控制风缸
B、制动缸
C、总风缸
D、作用风缸
参考答案:C
一I enjoyed a very good holiday in Shuangqiao.
-__________.
A.I am glad to hear that
B.It’s my pleasure
C.Congratulations
D.That’s very nice of you
飞机向台飞行,如果一直沿航线飞行,则测量出的QDM应等于().
A.航向
B.偏流角
C.航线角