2. (30 pts) A hot surface at 300C is to be cooled by attaching straight aluminum rectangular fins (k=260 W/mK) with 30 mm length, 60 mm width and 5 mm base thickness. Fins are exposed to an ambient air condition of 35C and heat transfer coefficient is 45 W/m2. K. If there are 2500 fins per m surface area, calculate; a. The heat transfer rate from a single fin. b. The increase in the rate of heat transfer per m surface area as a result of attaching 2000 fins. c. Determine the overall effectiveness of the fins. 3. (20 pts.) Methanol at 40C flows over the upper surface of 3-m-long flat plate whose temperature 20C surface temperature with a velocity of 3 m/s. Determine the total drag force and heat transfer per unit width of the entire plate. 4. (20 pts.) In a horizontal copper pipe with a 5-cm diameter and a length of 30 meters, water is flowing steadily at a rate of 8 L/s. Determine the pressure drop and the pumping power needed to overcome the pressure drop. Assume flow is fully developed. Is this a good assumption?