Polar Water, a company that delivers bottled water, is considering three investment opportunities. The expected returns for each of the projects are as follows: buying a new delivery van, 12%; computer training for its office staff, 9%; and defensive driving training for its drivers, 8%. If the current interest rate is 7%, the firm should invest in
◦ only the purchase of a new delivery van.
◦ the purchase of a new delivery van and computer training for its office staff.
◦ all of the projects.
◦ none of the projects.