一 has this food store been in business?
一 Since 2008.
A:How long
B:How often
C:How old
D:How soon
不等式组 3x-1⩾52x+4<x+7的解集为( )
在①a4•a2②(﹣a2)3③a12÷a2④a2•a3⑤a3+a3中,计算结果为a6的个数是( )