1.1℃时,海水的冰缘已在()海里之内 ["50~150","150~300","100~150","300~450"]
EDFA属于以下哪一类设备() ["A、OM","B、OA","C、OD","D、OUT"]
冰量一般以()法度量,分为()级 ["10;8","8;10","8;8","9;9"]
冰情通报中,称为“冰岩”的其直径约为() ["30米以上","6~30米","2~6米","2米以下"]
在WDM系统中,OM/OD与OTU之间用什么连接?() ["光缆","软光纤或尾纤","同轴电缆","网线"]
电除尘器投入要具备哪些条件?