发电机灭火环管的喷水孔，要求正对（）
A.定子线圈
B.磁极
C.电缆
D.定子线圈端部
参考答案：D
幸福小学共有m名学生，其中男生230名，女生______名．
What is TRUE concerning frapping lines?（）
A.They are used to steady a lifeboat when lowered
B.They are normally attached to the davit span
C.They are needed only on radial davits
D.They are used to clear the puddings
