同温同压下，等质量的下列气体所占的体积最大的是[ ]
A. O2
B. CH4
C. CO2
D. SO2
答案：B
—Your coat is very nice. —____ .
A．No, it isn’t.
B．You are right.
C．I think it’s mine.
D．Thank you.
什么是无线电导航技术？
