QUESTION 4 (PO2, CO2, C3) a) A flat cooking Pyrex pan at 200C was suddenly being dipped in an icy water at 15C. With a diameter of 50 cm and a thickness of 2 cm, assume that the temperature of the flat Pyrex is spatially uniform and the temperature gradients within it are negligible. Determine the time needed for the pan to reach the room temperature at 25 C if the radiation effect is negligible. Given that the convection heat transfer coefficient, pan density and pan heat capacity are 200 W/mK, 2225 kg/m and 835 J/kg.K, respectively. (10 marks)