Fins are frequently installed on tubes by a press-fit process. Consider a circumferential aluminum fin having a thickness of 1.0 mm to be installed on a 2.5-cm-diameter aluminum tube. The fin length is 1.25 cm, and the contact conductance may be taken from Table 2-2 for a 100-μ in ground surface. The convection environment is at 20ºC, and h = 125 W/m2 · ºC. Calculate the heat transfer for each fin for a tube wall temperature of 200ºC. What percentage reduction in heat transfer is caused by the contact conductance?