A:She is doing her homework.
B:She is cleaning her room.
C:She is singing.
若(x﹣2)2+|y+1|=0,则x+y等于( )
已知圆台的上、下底面半径分别是2、6,且侧面面积等于两底面面积之和.
(1)求该圆台母线的长;
(2)求该圆台的体积.