You need a new car and the dealer has offered you a price of 20,000, with the following payment options: (a) pay cash and receive a 2,000 rebate, or (b) pay a 5,000 down payment and finance the rest with a 0% APR loan over 30 months. But having just quit your job and started an MBA program, you are in debt and you expect to be in debt for at least the next 2.5 years. You plan to use credit cards to pay your expenses; the one you have has a fixed rate of 15% APR (monthly). Which payment option is best?