For the following problems, consider a pool shaped like the bottom half of a sphere, that is being filled at a rate of 25 ft³/min. The radius of the pool is 10 ft. The formula for the volume of a partial hemisphere is V=h/6(3r^2+h^2) where h is the height of the water and r is the radius of the water.

Find the rate at which the depth of the water is changing when the water has a depth of 1 ft.