In a recent year, Toyota was offering the choice of a .9% loan for 60 months or

Question:

In a recent year, Toyota was offering the choice of a .9% loan for 60 months or $500 cash back on the purchase of an $18,000 Toyota Corolla.
(a) If you take the .9% loan offer, how much will your monthly payment be?
(b) If you take the $500 cash-back offer and can borrow money from your local bank at 6% interest compounded monthly for 5 years, how much will your monthly payment be?
(c) Which of the two offers is more favorable for you?