接入380V配电网的储能系统，当接入点频率低于（）HZ时，应停止充电。
A.49.5
B.49.6
C.49.7
D.49.4
参考答案：A
具有中性点放电间隙的220kV变压器，其零序过压保护动作电压一般取（）
A、150V
B、180V
A 28-year-old nurse has complaints of itching and a rash of both hands. Contact dermatitis is initially suspected. The diagnosis is confirmed if the rash appears
A．erythematous with raised papules.
B．dry and scaly with flaking skin.
C．inflamed with weeping and crusting lesions.
D．excoriated with multiple fissures.
