A:x1=0,x2=4
B:x1=1,x2=5
C:x1=1,x2=﹣5
D:x1=﹣1,x2=5
如图所示,下列条件中,能判断AB∥CD的是( )
—Who can help me carry the heavy box?
—I think David is _______ to do it. But the door is ______for him to go through.