A hot surface of a chemical reactor at \(90^{\circ} \mathrm{C}\) is to be cooled by attaching \(2.5 \mathrm{~cm}\) long, \(0.3 \mathrm{~cm}\) diameter aluminum pin fins \(\left(k=237 \mathrm{~W} / \mathrm{m}-{ }^{\circ} \mathrm{C}ight)\) to it. There are total 28000 number of fins. The temperature of the surrounding medium is \(25^{\circ} \mathrm{C}\), and the heat transfer coefficient on the surface is equal to \(30 \mathrm{~W} / \mathrm{m}-{ }^{\circ} \mathrm{C}\). Determine the overall effectiveness of the finned surface. Assume the fin end to be insulated.