《水质丙烯晴的测定月相色谱法》(HJ/T73-2001)规定,采用单点外标法定量测定丙烯腈,标准溶液的进样体积与试样体积应相同。
参考答案:对
I have _____ a member of the music club for many years.
A. been B. became C. joined
在检查线路正确,视频设备没问题的情况下,有的球机不能旋转的可能原因?