单项选择题
A.0.47mm2,4.86mm2 B.0.81mm2,4.86mm2 C.0.47mm2,9.72mm2 D.0.81mm2,9.72mm2
A.23.773kA B.41.176kA C.21.396kA D.24.905kA
A.10s B.30s C.60s D.120s