Finally, tired _____ happy, we took the subway back home.[ ]
A. and
B. but
C. or
D. more
答案:B
简述消防设备应急电源功能调试的内容和要求。
()DTX对下列哪个信道起作用?
A.BCCH
B.TCH
C.SDCCH
D.CCCH