光时域反射仪可测量出哪些内容?
参考答案:
光时域反射计可以测量如下内容:1光纤断裂点的位置,2光纤的衰减,3接头损耗,4光纤的长度,5光纤沿长度的衰减分布情况。
I wonder why Jack always gets good marks when he does only ________ the others.
A.half as much as
B.as much as half
C.half as many as
D.as many as half
一般情况下,重点对账客户应按()发送对账单,每年()随机抽取部分客户面对面对账一次。
A.月;定期
B.月;不定期
C.季;定期
D.季;不定期