如磁钢顶面距钢轨面偏低，则可能导致（）。
A.磁头输出信号偏低
B.轮压伤磁钢
C.计轴计辆错
D.引起丢轴
E.多轴
参考答案：A, C, D
— Can I pay the bill by check?
— Sorry, sir. But it's the management rules of our hotel that payment ______be made in cash.
A．shall
B．need
C．will
D．can
磁盘上的文件以( )为单位读写。
A．块B．记录C．磁道D．柱面
