A.120 B.130 C.140 D.150
A.1~2 B.3~4 C.4~5 D.5~6
A.電纜長(zhǎng)度 B.熱穩(wěn)定系數(shù) C.電纜經(jīng)濟(jì)壽命 D.電纜截面