——How was your summer camp, Ben? ——________. I made so many friends.
A:Of course
B:Not really
C:Boring
D:Fantastic
如图,点P是线段AB上的点,其中不能说明点P是线段AB中点的是( )
已知关于x,y的方程组3x+y=1+3ax+3y=1-a的解满足x+y<0,则a的取值范围是( )