已知集合$M=\left\{x|\left|x-7\right|<9\right\}$，$N=\left\{x|y=\sqrt{9-x^2}\right\}$，且$M,N$都是全集$U$的子集，则右图中阴影部分表示的集合是        （   ） 

    Bob and Sue are in the same school，1they are in different classes.After school，Bob and Sue often play games with their friends.Class begins at eight in the morning.Now Bob and Sue are in2own classrooms.They are3to their teachers.Bob is studying English.Sue is having an art lesson.She4to make a birthday card5her mother.

    Her teacher Miss Li is helping her.

从1956年到1966年,我国在探索社会主义建设道路时期取得的成就是(    )

①石油全部自给   ②开始改变工业落后面貌

③修建了武汉长江大桥   ④第一颗原子弹爆炸成功

某班去看演出，甲种票每张24元，乙种票每张18元．如果35名同学购票恰好用去750元，甲乙两种票各买了多少张？