Drag and drop an answer to each box to correctly complete the explanation for deriving the formula for the volume of a sphere. For every corresponding pair of cross sections, the area of the cross section of a sphere with radius r is equal to the area of the cross section of a cylinder with radius Response area and height 2r minus the volume of two cones, each with a radius and height of r. A cross section of the sphere is Response area, and a cross section of the cylinder minus the cones, taken parallel to the base of cylinder, is Response area. The volume of the cylinder with radius r and height 2r is Response area, and the volume of each cone with radius r and height r is 13πr3. So the volume of the cylinder minus the two cones is Response area. Therefore, the volume of the cylinder is 43πr3 by Cavalieri's principle.