Q3. (A) A glass tube, 1 m long, 2 mm thick with 20 mm outside diameter is filled with water at 10°C. The convective heat transfer coefficient between the water and inner surface of the tube is 200 W/(m².°C). The ambient temperature is 40°C and the heat transfer coefficient on the outside of the tube is 25 W/(m².°C). Neglecting the heat loss from the tube ends, calculate the time required for the water to reach a temperature of 20°C, find the equilibrium temperature.