a box with a square base and open top must have a volume of 70304 c m 3 cm3 . we wish to find the dimensions of the box that minimize the amount of material used. first, find a formula for the surface area of the box in terms of only x x , the length of one side of the square base. [hint: use the volume formula to express the height of the box in terms of x x .] simplify your formula as much as possible.