BC类干粉灭火器适用于扑救易燃气体、液体和电气设备的火灾。
参考答案：对
He _____ in the exam. The teacher_____think he _____ his best. [ ]
A. failed, didn't, did
B. failed, /, didn't
C. fails, didn't, do
D. failed, /, did
断层面与地面的交线称为（）。
A.断层线
B.断层
C.断面
D.断层的两盘
