The tubes in a shell and tube heat exchanger are 10 ft long. The liquid in the tubes is ammonia at an average temperature of 110°F. The flow rate of the ammonia entering the heat exchanger is 120,000 lbm/hr. The heat exchanger tubes are 1-in 14 BWG tubes on a 1¼-in triangular pitch. The shell diameter is 12-in. Determine the pressure drop (psi) through the tube side of the heat exchanger for a singlepass, 2-pass, and 4-pass tube configuration.