A rectangular fin of 30 cm length, 30 cm width, and 2 mm thickness is attached to a surface at 3000C. The fin is made of aluminium (k = 204 W/mK) and is exposed to air at 300C. The fin end is uninsulated and can lose heat through its end also. The convection heat-transfer coefficient between the fin surface and air is 15 W/m2K. Determine (a) the temperature of the fin at 30 cm from the base, (b) the rate of heat transfer from the fin, and (c) the fin efficiency.