"Pin fins" of aluminum are to be compared in terms of their relative performance as a function of diameter. Three "pins" having diameters of 2, 5, and 10 mm with a length of 5 cm are exposed to a convection environment with T∞ = 20ºC, and h = 40 W/m2 ∙ ºC. The base temperature is 200ºC. Calculate the heat transfer for each pin. How does it vary with pin diameter?