A farmer installed a tank for the purpose of keeping the hot water for his residential house in the farm. The tank is made of mild steel of wall thickness 10 mm and contains water at 90oC. Calculate the rate of heat loss per m2 of tank surface area when the atmospheric temperature is 15oC. The thermal conductivity of mild steel is 50 W/mK , and the heat transfer coefficients for the inside and outside of the tank are 2800 and 11 W/m2 K , respectively. Calculate also the temperature of the outside surface of the tank.