两圆的圆心距为5,两圆的半径分别是方程x2 -4x +3=0的两个根,则两圆的位置关系是()
A:相交
B:外离
C:内含
D:外切
①秦朝的徭役繁重 ②秦朝的赋税很重 ③秦朝统一度量衡 ④秦朝的刑法残酷
下列有关细胞构成生物体的叙述中不正确的是( )
If we spend too much time on the Internet, we won't have enough time to study. , working on computers too long may cause headaches or sore eyes.