In solvent production plant, raw material stream heated from 20\deg C to 45\deg C by using 90\deg C hot process stream. For this purpose, counter-current plate type heat exchanger used that has 12m^(2) heat transfer area. Raw material and process stream flow rates are given as 10k(g)/(s) and 21k(g)/(s), respectively. Assume there is no heat loss to environment, stream heat capacities are constant and F=1.,(C_(p, raw )=4.2(kJ)/(k)g.K,C_(p, process )=2.50(kJ)/(k)g.K) a