题型:填空题 关于电磁波及其应用,下列说法中不正确的是( )A.电磁波在真空中传播的速度与光速相同B.移动电话只能接收电磁波,不能发射电磁波C.用三颗地球同步卫星就可以实现全球通信D.无线电波中,长波的频率小于短波的频率 查看答案
题型:填空题 I felt surprised that anyone of his intelligence ________ such an easy test.A.might have failed B.could have failedC.should have failedD.must have failed 查看答案