A box, with rectangular sides, base and top is to have a volume of 2 cubic feet. It has a square base. a. Express the surface area A of the box in terms of the width w of the base. A(w) = ft b. If the material for the base and top costs 20 dollars/ft and that for the sides costs 30 dollars/ft, express the total cost C as a function of the width. C(w) = $