用钢绞线做拉线时，其尾端用绑扎固定时，应整齐紧密，5股的钢绞线其缠绕长度应不小于（）mm。
A.80
B.100
C.150
D.200
参考答案：C
------Tony, are you listening to me ？
------Sorry sir, I to understand what you said just now.
A．try
B．was trying
C．tried
D．have tried
踏面圆周磨耗有什么害处？
