Diane Wallace bought a living-room suite on credit, signing an installment contract with a finance company that requires monthly payments of $55.53 for three years. The first payment is made on the date of signing and interest is 23% compounded monthly.

(a) What was the cash price?

(b) How much will Diane pay in total?

(c) How much of what she pays will be interest?

(d) Based on the cash price calculated in part (a), if the interest rate is changed to 20.3% compounded monthly, what is the new monthly payment?