One of the largest automobile dealers in the city advertises a 3-year-old car for sale as follows: Cash price $3575, or a down payment of $375 with 45 monthly payments of $93.41. Susan DeVaux bought the car and made a down payment of $800. The dealer charged her the same interest rate used in his advertised offer. How much will Susan pay each month for 45 months? What effective interest rate is being charged?