You must make a metal container with an open top in the shape of a cuboid, as shown in the following diagram. The container has height x metres and width y metres. The volume is 36 m3. Let A(x) be the outside surface area of the container. a) Find an expression for the area, A, in terms of x. b) Find dA dx c) Find the value of x when the area of the outside surface is minimized. Justify your