#10 A closed, rectangular box with a square base is to be constructed. 12 square inches of material is available (this is the surface area of the box). Find the dimensions of the box with the maximal volume. #11 A rectangular box with a square base and an open top must have a volume of 256 cubic inches. Find the dimensions of the box that will minimize the amount of material used (minimize the surface area of the box). #12 If a snowball melts so its surface area decreases at a rate of 1cm / min , find the rate at which the diameter decreases when the diameter is 6 cm. #13 The radius of a sphere increases at a rate of 3 in/sec. How fast is the volume increasing when the diameter is 24in