A:two thirds; wear; 60 percent
B:two thirds; wear; 60 percent
C:two third; wears; 60 percent
D:two third; wears; 60 percent
右面图片是第一次世界大战时各国的征兵宣传海报,各国参加战争的共同目的是( )
按此规律推断,以s、n为未知数的二元一次方程是____.