单项选择题
A.1Ω B.2Ω C.3Ω D.4Ω
A.1.25m B.2.25m C.2.5m D.3.25m
A.75mm B.100mm C.150mm D.300mm
A.15m B.30m C.45m D.60m
微信扫一扫,加关注免费搜题