A:聚族而居
B:原始农业
C:贫富分化
D:采集狩猎
已知双曲线 x2m-y2n=1(mn≠0)的离心率为2,有一个焦点恰好是抛物线y2=4x的焦点,则此双曲线的渐近线方程是( )
Fresh food is good for you . But you have to _______it first because sometimes it is a little dirty.
计算a2(2a)3﹣a(3a+8a4)的结果是( )