Problem 2 Five projects are being evaluated over a 3-year planning horizon. The following table gives the expected returns for each project and the associated yearly expenditures. 8 Project 1 2 3 4 5 Available funds ($ million) Expenditures ($ million)/year 1 2 3 5 1 4 7 10 3 9 2 7 4 8 6 10 25 25 25 Returns ($ million) 20 40 20 15 30 1 a) Formulate an IP that helps in identifying the projects which should be selected over the 3-year planning horizon. b) Modify the formulation such that project 5 must be selected if either project 1 or project 3 is selected. c) Modify the formulation such that projects 2 and 3 are mutually exclusive