A:①②③④
B:①②③
C:①③
D:①③④
如图所示的电解槽接入电路后,在t秒内有n1个1价正离子通过溶液内截面S,有n2个1价负离子通过溶液内截面S,设e为元电荷,以下说法正确的是( )
Many young people, most of ____were well-educated, headed for remote regions to chase their dream.
读 《为人民服务》,选择下面说法正确的一项( )。