A hollow sphere of aluminum, with an inside radius of 0.01 m and an outside radius of 0.02 m has its outer surface maintained at 100°C. Cold water at 0°C is available to cool the inside surface of this spherical shell, and its flow is controlled at a rate that serves to maintain the inside surface at 10°C. Assuming that the inside heat transfer coefficient between the water and the inner surface is very high, and that the water within the region is very well mixed, what is the required flow rate of the cooling water?