能够完全避免电磁干扰的是 (34) 。在一般通信要求下,双绞线在 (35) 的范围内信号不用放大。
A.光纤 B.同轴电缆 C.双绞线 D.75欧姆同轴电缆
参考答案:A
O'Neal works hard. He is often seen _______ heavily before his teammates have even arrived at practice.
A.sweated
B.to be sweated
C.sweating
D.being sweated
起升机构制动器失效时应()
A.把控制手柄置于工作档位
B.鸣铃示警
C.注意升降时的上、下限位置
D.在起升大、小车控制手柄时应逐步推挡,不可快速扳转