计算:(1)(-5a2b)(-3a);
(2)(2x3y)2·x3y+(-14x6)·(-xy)3.
若x,y互为相反数,且(x+2)2-(y+2)2=4,则x=________,y=________.
计算:=________.
如果2m=5,2n=3,那么2m+n=________,2m-2n=________.
若(2x-3)(5-2x)=ax2+bx+c,则a+b+c=_____.
计算:(1)(π-3.14)0×=________;
(2)(-2+3b)2=__________________.