An in-line tube bank is constructed of 1 inch diameter tubes, with 15 rows transverse to the flow, 7 rows in the floe direction. The tubes are kept at 194 F. Atmospheric air enter the system at 68 F and velocity (upstream of the tubes) of 40 ft/sec. The tubes have center to center distance of 1.5 inches in the flow direction, 2 inches normal to the flow. Calculate the heat transfer / foot of the tube.