无缝线路固定区累计位移量大于（）时，应及时上报工务段查明原因，采取相应措施。
A.8mm
B.9mm
C.10mm
D.11mm
参考答案：C
A．光传播的速度总是3.0×108m/s
B．太阳光是种偏振光
C．同一色光在不同介质中传播，频率不变
D．激光炮的威力强大，这是利用了激光的高相干性
In each inflatable rescue boat，what piece of equipment is provided to make quick，emergency，temporary repairs to a large hole in a raft?（）.
A.No equipment is provided
B.Glue and rubber patches
C.Several various-sized sealing clamps
D.Self-adhesive rubberized canvas patches
