Air at 50 degree C and 1 atm is cooled by flowing through an underwater duct. The water is at 5 degree C. The duct is 20-cm-diameter and 12-m-long. The mean velocity of air is 7 m/s. If the average heat transfer coefficient is 85 W/m2K and the tube temperature is nearly equal to the water temperature, determine the rate of heat transfer. Air properties at the anticipated average temperature of 30 degree C are: density