实施简单抽样的方法有____、____.
(Ⅰ) (14)−12+823−62514 ;
(Ⅱ)(log2125+log425+log85)(log52+log254+log1258).
Which do you prefer to use to keep in touch with your friends, QQ______ WeChat?
中国近代民族工业最早出现于( )