10.You have the alternative of paying for university fees today for a payment of $15,000 or, you can select a payment plan where you pay $8,000 in 6 months from today and another $12,000 in exactly 18 months from today. If the interest rate is 9.9%p.a. compounding monthly, what is the advantage that the payment plan has over the upfront payment?

18.Calculate the nominal interest p.a. compounded half-yearly that is equivalent to 7.2% p.a. compounded quarterly. (Correct your answer to the nearest 0.01%, e.g. 2.12%)