题目

同温同压下，同体积的甲乙两种气体的质量比是17:14。若乙气体是CO，则甲气体是（   ） A．H2S   B．HCl    C．NH3   D．Cl2 答案：A12、I ________ ride a bike to school. But this morning I took a taxi because I got up late. A．never         B．sometimes           C．seldom          D．usually