如果x=135679×975431,y=135678×975432,那么( )
A:x<y
B:x>y
C:x=y
D:无法确定
已知x,y,z∈R,且x﹣2y+2z=5,则(x+5)2+(y﹣1)2+(z+3)2的最小值是( )
I don't know ______.