单项选择题
A.0.21% B.0.60% C.0.77% D.2.11%
A.1:200~1:400 B.1:200~1:500 C.1:300~1:500 D.1:200~1:700
A.聚氯乙烯内护套电缆 B.不滴油纸绝缘电缆 C.细钢丝电缆 D.纤维线包电缆