____(结果用数值表示).
下图是表示气体微粒的粒子模型,图中“○”和“●”分别表示氧原子和氢原子.其中能保持氢气化学性质的是粒子模型是( )
—Why can't you give me another chance?
—________, but I don't think you are good at management.