A.10% B.5% C.15% D.30%
A.MULTIMETER B.LOCAL C.RESISTANCE D.CONTACT
A.n=50f/p B.n=60f/p C.n=50p/f D.n=60p/f
A.绝缘 B.散热 C.灭弧 D.防潮
A.烧坏; B.不工作; C.工作正常; D.完好。
A.1.3 B.1.5 C.1.6 D.2.0