【单选题】电磁波测距的基本原理是( )(说明:c为光速,t为时间差,D为空 间距离)。
【单选题】All the following can damage hearing EXCEPT______.
B.
too much moderate noise for a long time
C.
intense noise for even a short time
D.
moderate noise for a short time
【单选题】电磁波测距的基本原理是:( )(说明:c为光速,t为时间差,D为空间距离)。
【单选题】There is ______ traffic and ______ peo ple in the street at the moment. [ ]
【单选题】电磁波测距的基本原理是:()。(说明: c为光速,为时间差,D为空间距离)
【单选题】So many people violate traffic regulations that we ____ put too much emphasis on the importance of traffic safety.
【单选题】------Don’t drive so fast please. There is _________traffic at this time of the day.
【单选题】电磁波测距的基本原理是:( )(说明:c为光速,t为时间差,D为空间距离)。
【单选题】I don't like those big cities which have got ____ people and ____ traffic. [ ]
【单选题】电磁波测距的基本原理是:( )(说明:c为光速,t为时间差,D为空间距离)。