A:都有酸根离子
B:都有氢离子
C:都有氢元素
D:都使紫色石蕊变红
﹣2×4的结果是( )
— Did you listen to the program yesterday?
— Yes. I can't believe I heard her singing ______ the radio.
下列关于亚洲的说法,不正确的是( )
三峡水电站的水坝高185m,当水库水位为175m时,坝底受到水的压强是多大?(g=10N/kg)