自然伽马仪器电缆驱动器的作用是对脉冲信号进行功率放大和实现与电缆的（）。
参考答案：阻抗匹配
It isn’t warm enough him his coat. [ ]
A. to make; take off
B. make; to take off
C. to make; put on
D. make; to put on
下列物质中不能在氧气里燃烧的是[ ]
A. 空气
B. 木炭
C. 红磷
D. 铁
