Problem 2 (Required, 25 marks) Tina borrows an amount $500000 from the bank and agrees to repay the loan by 4n level monthly payments (with amount X) made at the end of every month. The first repayment will be made 1 month after today. You are given that The loan charges interest at an annual nominal interest rate 5.9% convertible continuously. The outstanding balance at 25th repayment date is OLBs = 397021.93. (a) Calculate the interest due and principal of (n + 1) th repayment. ( Hint: Find X first) (b) Just after nth repayment, Tina decides to increase the monthly repayment amount to Y such that the remaining outstanding balance can be repaid completely by 2n repayments (instead of 3n repayments) By speeding up the repayment process, Tina can save some interest payment. Calculate the amount of interest saved by adopting this new repayment schedule. ( Hint: To do so, you need to calculate the total amounts of interest payments under the old repayment schedule and new repayment schedule respectively.)