1. A heap of rubbish in the shape of a cube is being compacted into a smaller cube. Given that the volume decreases at a rate of 5 cubic meters per minute, find the rate of change of an edge, in meters per minute, of the cube when the volume is exactly 64 cubic meters.
2. A rectangle is inscribed in a circle of radius 4 inches. If the length of the rectangle is decreasing at the rate of 3 inches per second, how fast is the area changing at the instant when the length is 5 inches?