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 construction costs, Maureen needs to invest some of the companys money now to meet these future cash flow needs. Maureen may purchase only three kinds of financial assets, each of which costs $1 million per unit. Fractional units may be purchased. The assets produce income 5, 10, and 20 years from now, and that income is needed to cover minimum cash flow requirements in those years, as shown in the following table (where all quantities are ion millions)

Year	Income per unit of asset	Minimum cash flow required
Asset 1	Asset 2	Asset 3
5	$8	$4	$2	$1,600
10	$2	$2	$4	$400
20	$0	$6	$8	$1,200

Maureen wishes to determine the mix of investments in these assets that will cover the cash flow requirements while minimizing the total amount invested.

1. Formulate a linear programming model for this problem on a spreadsheet. Use the spreadsheet to check the possibility of purchasing 100 units of asset 1, 100 units of asset 2, and 200 units of asset 3. How much cash flow would this mix of investments generate and what would be the total amount invested?
   1. Cash 5 years from now
   2. cash ten years from now
   3. cash twenty years from now
   4. total amount invested
2. Use Solver to find an optimal solution. What is the optimal solution? (Enter numbers in millions and do not include dollar signs. For example, for one hundred and fifty million dollars, enter 150.)
   1. asset 1 =
   2. asset 2 =
   3. asset 3 =