中兴开关电源ZXDU75的交流市电输入方式（）。
A、单相三线制
B、三相四线制
C、四相五线制
D、单相二线制
参考答案：A
At no time the rules of the game.It was unfair to punish them.
A．they actually broke
B．do they actually break
C．did they actually break
D．they had actually broken
鼓泡塔反应器的高径比一般（）
A、较大
B、较小
C、相等
D、根据情况而定
