Question: (11 pts) An investment company owns five companies that have the following estimated returns (in millions of dollars) if sold in 1 of the next 3 years:

The company must sell at least $25 million worth of assets in year 1, $30 million in year 2 and $35 million in year 3. They desire a plan for selling the five companies during the next 3 years to maximize return (determine which year to sell each company). Formulate an integer programming model (decision variables: 0 if not sold, 1 if sold) for this problem and solve it using the computer.