某工程按全等节拍流水组织施工,共分4道施工工序,3个施工段,估计工期为72天,则其流水节拍应为()。
A.6天
B.9天
C.12天
D.18天
参考答案:C
We _____ Xiao Li since she was a little girl.[ ]
A. know
B. had known
C. have known
D. knew
误码率描述了数据传输系统正常工作状态下传输的( )。
A.安全性
B.效率
C.可靠性
D.延迟