A container made from thin metal is in the shape of a right circular cylinder with height \(h\) cm and base radius \(r\) cm. The container has no lid. When full of water, the container holds 500 cm³ of water.
Show that the exterior surface area, \(A\) cm², of the container is given by
$$A = \pi r^2 + \frac{1000}{r}.$$
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