Kevin borrowed a 25-year mortgage loan of $8,000,000 from Hang Seng Bank (HSB) to purchase a flat in North Point 6 years ago. The interest rate was made at "Prime rate minus 2.7%". The loan was a fully-amortizing one and required monthly payments. (a) Suppose the prime rate was 5% at loan origination and had been remaining constant in the last 6 years. Calculate Kevin's monthly payments and his loan balance at the end of Year 6. (4 marks) (b) Find the total payments and interest expenses of Kevin in the last 6 years. (4 marks) (c) Suppose now the prime rate has fallen to 4.75% and Kevin can refinance by borrowing another loan from Chong Hing Bank (CHB) at "Prime rate minus 2.75%" for a term of 19 years. However, there is a loan origination fee of $8,000 charged by CHB. Find Kevin's new monthly payments if he borrows the new loan. (3 marks) (d) What is the annual rate of return (benefit) enjoyed by Kevin through refinancing? (4 marks)