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4) (20 points) A furniture store is offering the following two payment options for a new designer living room set that costs $15,000. You can pay cash now or you can choose the store's installment offer equal payments of $625 payable at the end of each month starting one month from now over a 2-year period at 0% interest rate plus a small monthly processing fee of $40 that needs to be paid along with each monthly payment. I claim that you will end up paying an effective annual rate of approximately 6.17 % if you choose the installment offer. Do you agree with me? Show work to support your