A.0.5m B.1.0m C.1.5m D.1.8m
A.IΔ>30mA,TΔ=0.1S B.IΔ=30mA,TΔ>0.1 C.IΔ>30mA,TΔ>0.1S D.IΔ>30mA,TΔ>0.1S,IΔ²TΔ≯30mA20.1S
A.1.5m B.1.0m C.0.8m D.0.5m