A $280000 mortgage is to be amortized by making monthly payments for 22.5 years. Interest is 8.2% compounded semi-annually for a four-year term. a) Compute the size of the monthly payment. b) Determine the balance at the end of the four-year term. c) If the mortgage is renewed for a five-year term at 7.66% compounded semi-annually, what is the size of the monthly payment for the renewal term?