Help solve ONLY (b) with excel. Please show step by step

2-40. Fox Enterprises is considering six projects for possible construction over the next four years. Fox can undertake any of the projects partially or completely. A partial undertaking of a project will prorate both the return and cash outlays proportionately. The expected (present value) returns and cash outlays for the projects are given in the following table. Cash outlay ($1000) Year 2 Year 3 Project Year 1 Year 4 22 10.5 8.3 10.2 3.1 42 12.6 14.2 10.5 10.1 7.8 Return ($1000) 32.40 35.80 17.75 14.80 18.20 12.35 5.0 6.3 12.3 9.2 8.3 6.9 5.1 Available funds ($1000) 60.0 70.0 35.0 20.0 (a) Formulate the problem as a linear program, and determine the optimal project mix that maximizes the total return using AMPL, Solver, or TORA. Ignore the time value of money. (b) Suppose that if a portion of project 2 is undertaken, then at least an equal portion of project 6 must be undertaken. Modify the formulation of the model, and find the new optimal solution