Follow step-by-step the methodology followed in class to design a heat exchanger network that minimizes both number of exchangers and utility usage (find the temperature interval diagram, cascade diagram, draw H-T diagram, calculate the minimum heating and cooling utilities required and the pinch point temperatures, and an optimized design of a heat exchanger network on both the hot and cold sides of the pinch): A) Assume a Tmin=20C (15 points)