总容量（）kvar以上的10kV并联电容器应采用断路器控制和保护。
A、100
B、200
C、300
D、400
参考答案：C
Yang Liwei was a student at this flight school from 1983 to 1987, he studied very hard and was made chairman of the Students’ Union.
A．during which time
B．for which time
C．during whose time
D．by that time
设，则A的伴随矩阵A*为（）。
A．A
B．B
C．C
D．D
，则A的伴随矩阵A*为（）。