When he was ill, he well by his grandma.
A:is looked after
B:will be looked after
C:was looked after
现将10gA和足量的B混合加热,A和B发生化学反应,10gA完全反应后生成8gC和4gD,则参加反应的A与B的质量比是( )
我国是一个统一的多民族国家,生活着多少个民族?( )