无缝道岔作业当天,封锁路前每隔一段距离拆卸一根轨枕上的扣件。
参考答案:对
. It is said that in Australia there is more land than the government knows _______.
A.it what to do with
B.what to do it with
C.what to do with it
D.to do what with it
APU引气页面,方框内的引气压力显示,什么时候显示琥珀色()
A.当ADIRS 1(大气数据/惯性基准系统1)不可用或选择关断(OFF)位
B.ECB数据无效或未被传送时
C.以上都对