[TOTAL: 40 PTS] Liquid benzene is to be cooled from 70C using water entering at 15C and leaving at 35C in a countercurrent double pipe heat exchanger composed of 3/4" Sch. 40 and 1.5 " Sch. 40 rough steel pipes. Entering velocity of liquid benzene in the inner pipe is 2.5m/s. If the length of the heat exchanger is 20 meters, find: a. The cooling water rate (20 pts) b. The exit temperature of benzene ( 20pts) The heat transfer coefficient of water can be calculated by: h=1049[1.352+0.02(T273.15)](D0.200.8)