A.建設(shè)單 B.電話業(yè)務(wù)單 C.寬帶業(yè)務(wù)單 D.ITV業(yè)務(wù)單
A.22dBm B.24dBm C.26dBm D.28dBm
A.1 B.2 C.3 D.4