Acone is constructed by cutting a sector from a circular sheet of metal with radius 20. the cut sheet is then folded up and welded. find the radius and height of the cone with maximum volume that can be formed in this way. a circular sheet of metal with radius 20 units has a sector removed. a right circular cone has a radius labeled r and a height labeled h. the slant height of the cone is 20 units. 20 20 h r write the objective function relating v and h in a form that does not include r. vequals startfraction 400 pi h over 3 endfraction minus startfraction pi h cubed over 3 endfraction (type an expression. type an exact answer, using pi as needed.) the interval of interest of the objective function is left parenthesis 0 comma infinity right parenthesis