使用过的工作票由()和牵引变电所工长负责分别保管。
A.工作领导人
B.值班员
C.发票人
D.作业人员
参考答案:C
I am wondering _________. [ ]
A. why did he come to school late
B. why he came to school late
C. that he came to school late
D. why was he late for school
交换机端口在什么STP状态下传输用户数据并获知MAC地址()
A.阻塞
B.学习
C.禁用
D.侦听
E.转发