A.5Ω B.1Ω C.25Ω D.10Ω
A.50Hz B.51±0.2Hz C.51±0.5Hz D.51±0.1Hz
A.-0.0005%≤比值差≤+0.0005% B.-0.0001%≤比值差≤+0.0001% C.-0.01%≤比值差≤+0.01% D.-0.001%≤比值差≤+0.001%A