单项选择题
A.ΔU%U2/100SeB.ΔU%100/U2SeC.100Se/ΔU%U2D.100U2/ΔU%Se
A.(KeU1-UB)/U1B.(KeU2-UA)/U1C.(U1-UB)/KeU1D.(U2-UA)/KeU2
A.t1〉t2B.t1=t2C.t1〈t2D.t1〉3t2