please answer question 39

39. Investing Mary Dodge deposits $12,000 at the end of each year for 9 years in an investment account with a guaranteed interest rate of 6% compounded annually. (a) Find the value of the account at the end of the 9 years. (b) Mary's sister works for an investment firm that pays 5% compounded annually. If Mary deposits money with this firm instead of the one in part (a), how much will she have in her account at the end of 9 years? (c) How much would Mary lose or gain over 9 years by invest- ing in her sister's firm