5. Use the Rule of 72 to estimate the investment's doubling time and then determine the actual doubling time. Compound Principal (P) ($) Interest Rate per Annum (%) 80 000 7.2 A. 10 years; 9.97 years B. 10 years; 9.71 years Compounding Frequency quarterly Term 15 years C. 10 years; 10.2 years D. 10 years; 9.63 years 6. Determine the present value of a 2-year GIC (Guaranteed Investment Certificate) with an interest rate of 2%, compounded annually, if the future value is $1326.51. A. $1200 B. $1250 C. $1275 D. $1300 7. Determine the future value of monthly payments of $200 into an account that pays 4.6% interest, compounded monthly, for 15 years. A. $56 879.79 B. $46 538.01 C. $64 636.13 D. $51 708.90 8. For 3 years, regular weekly payments of $50 are deposited into an account that interest weekly. If the final value of the account is $8600, what was the interest rate? A. 6.51% B. 6.43% C. 6.23% D. 6.45% compounds