襄阳公园“鸭蛋”设计长边有()米。
A、50.0
B、110.0
C、200.0
D、400.0
参考答案:B
The headmaster told the boy________the angry teacher, but he refused to. [ ]
A. to apologize
B. apologize to
C. to apologize for
D. to apologize to
A.电流表的示数为3/11 A
B.通过灯泡的电流的频率为50Hz
C.电流表的示数为3/22 A
D.理想变压器原、副线圈匝数之比为2:1