In a production facility, large brass plates of 4 cm thickness that is initially at a uniform temperature of 20C are heated by passing them through an oven that is maintained at 600C (Fig. 420). The plates remain in the oven for a period of 7 min. Taking the combined convection and radiation heat transfer coefficient to be h=357 W/m2 C, determine the surface temperature of the plates when they come out of the oven.