71. Her family is all music lovers. ____________ 72. Her husband is a Swiss. Her parents are both Swisses. ____________ 73.
溶质质量分数分别为a%和5a%的H2SO4溶液等体积混合均匀后,则混合溶液中H2SO4的质量分数为 A.等于3a% B.等于6a% C.大于3a% D.小于3a%
通过下列化学反应不能达到目的的是( )A.制氯化铁:2Fe + 3CuCl2 = 2FeCl3 + 3Cu B.用稀硫酸除去炭粉中的少量氧化铜:CuO + H2SO4 = CuSO4 + H2O C.
阅读下面文段 ①从天而降的片片雪花给人们带来欢乐, 同时也给人们带来了无须额外投入的清洁能源。 ②专家推算, 10 万吨雪换算成等量
在如右图所示的电路中,当滑动变阻器的滑动头向上滑动时,A、B两灯亮度的变化情况为 ( )A.A灯和B灯都变亮B.A灯和B灯都变暗C.A灯变亮,B
They often paly _______ on the badminton court.A.badmintonB.basketballC.footballD.volleyball