A:社会福利保障程度高
B:就业机会多
C:文化设施短缺
D:交通便利
同一平面内的四条直线若满足a⊥b,b⊥c,c⊥d,则下列式子成立的是( )
He i____ all the “No Smoking” signs and lit up a cigarette.
选择适当的方法分解下列多项式(1)x2+9y2+4z2﹣6xy+4xz﹣12yz(2)(a2+5a+4)(a2+5a+6)﹣120.
The art club is for members only. You can't go in _______ you are a member.