5. (8 points) A pyramid with a square base of side length xom and height hem nas volume A -x/h. Consider a pyramid made of chocolate with side length x - 8cm resting on a warm metal plate. The chocolate is melting evenly along its base, so that its height h(t) at time t is is decreasing at a constant rate of 1cm/min. Its height is always 5/4 of its base side length. At what rate is the volume of the pyramid decreasing 5 minutes later? Use correct units