21. In how many years will money quadruple at 8% compounded quarterly? 22.A loan of $5000 taken out today is to be repaid by a payment of $2000 in nine months, a payment of $2500 in two years, and a final payment of $1200. If interest is 9% compounded monthly, when should the final payment be? 23. Yin Li deposited $800 into a savings account that compounded interest monthly. What nominal interest rate was earned on the investment if the balance was