What's he like?[ ]
A. He is 12.
B. He's tall and thin.
C. She's young.
答案:B
FAS系统中央与车站通信中断时,环调工作流程是什么?
发生不对称故障时,零序电压在()处最大。
A、振荡中心
B、非故障线路
C、故障点