A circumferential fin of rectangular profile is constructed of stainless steel with k = 43 W/m ∙ ºC and a thickness of 1.0 mm. The fin is installed on a tube having a diameter of 3.0 cm and the outer radius of the fin is 4.0 cm. The inner tube is maintained at 250ºC and the assembly is exposed to a convection environment having T∞ = 35ºC and h = 45 W/m2 ∙ ºC. Calculate the heat lost by the fin.