he shop is ______ from Monday to Friday. It’s ________ at weekends

A. opens; closed    B. open; close  C. open; closed    D opened; close

变压器过流保护动作跳闸原因（）。

A.保护范围的接地故障

B.本体发生相间故障

C.母线相间故障

D.下级线路故障越级