A.2cm B.3cm C.4cm D.5cm
A.大于19.2Ω/100m B.小于19.2Ω/100m C.大于等于19.2Ω/100m D.小于等于19.2Ω/100m
A.EIA/TIA-568 B.EIA/TIA-569 C.TSB36 D.TSB40