Consider a costbenefittrade-off problem having the following data. a. Formulate a linear programming model for this problem on a spreadsheet. b. Use the spreadsheet to check if (x1 , x2 , x3 ) = (1, 2, 2) is a feasible solution and, if so, what the daily cost would be for this diet. How many units of each nutritional ingredient would this diet provide daily? c. Take a few minutes to use a trial-and-error approach with the spreadsheet to develop your best guess for the optimal solution. What is the daily cost for your solution? d. Use Solver to find an optimal solution. e. Express the model in algebraic form. 3.12. Maureen Laird is the chief financial officer for the Alva Electric Co., a major public utility in the Midwest. The company has scheduled the construction of new hydroelectric plants 5, 10, and 20 years from now to meet the needs of the growing population in the region served by the company. To cover the Benefit Contribution per Unit of Each Activity Benefit 1 2 3 4 Minimum Acceptable Level P 2 1 4 3 80 Q 1 4 1 2 60 R 3 5 4 1 110 Unit cost $400 $600 $500 $300 a. Formulate a linear programming model for this problem on a spreadsheet. b. Make five guesses of your own choosing for the optimal solution. Use the spreadsheet to check each one for feasibility and, if feasible, for the value of the objective function. Which feasible guess has the best objective function value? c. Use Solver to find an optimal solution.