A spherical metal ball with an average mass of 1.7kg(k=0.45W/mC and =0.13106m2/s) initially at a uniform temperature of 15C are to be chilled in water at 10C. The convection heat transfer coefficient of the water is determined to be 440W/m2.C. Taking the average density of the metal ball to be 0.95g/cm3, determine the center temperature of the ball in 2h and 30min. (solve by using heissler charts) Please write the results clearly and explain how to obtain them. (30 Points)