4. (a) An association had a fund balance of 80 on January 1 and 60 on December 31. At the end of every month during the year, the association deposited 10 from membership fees. There were withdrawals of 5 on February 28; 25 on June 30, 80 on October 15; and 35 on October 31. Calculate the money-weighted rate of return for the year. 15 marks (b) An investor borrows an amount at an annual effective interest rate of 5% and will repay all interest and principal in a lump sum at the end of 10 years. She uses the amount borrowed to purchase a 1,000 par value 10- year bond with 8% semiannual coupons bought to yield 6% convertible semiannually. All coupon payments are reinvested at a nominal rate of 4% convertible semiannually. Calculate the net gain of the investor at the end of 10 years after the loan is repaid. 15 marks