三相变压器采用Y，△联接时，则联接组的标号一定是（）。
A、奇数
B、偶数
C、奇偶均可
D、一固定常数
参考答案：A
The police were seeking more information to find out _____ the rich merchant.
A．who was it that killed
B．who it was that killed
C．it was who killed
D．who was it killed
“十一五”时期，城乡区域发展趋向协调，城镇化率应提高到( )。
A．37%B．67%C．57%D．47%
