A25-cm-diameter stainless steel ball (rho = 8055 kg/m3, cp = 480 j/kg·°c) is removed from the oven at a uniform temperature of 300 °c. the ball is then subjected to the flow of air at 1 atm pressure and 25 °c with a velocity of 3 m/s. the surface temperature of the ball eventually drops to 200 °c. determine the average convection heat transfer coefficient during this cooling process. estimate the average rate of heat transfer.