Consider a hollow metallic sphere of inner radius R and outer radius R. In the metallic part of the sphere, which has a constant thermal conductivity of k, heat is produced due to electrical dissipation, at a constant volumetric flow rate of S. The inner (hollow) surface of the sphere is completely insulated. At the outer surface of the sphere, heat is convectively transferred to a cooling fluid, whose bulk temperature is Th. obeying Newton's law of cooling with constant heat transfer coefficient h. a) Obtain an expression for the steady temperature distribution in the metal. b) Calculate the rate of heat loss to the surroundings