The Grewals agreed to monthly payments on a mortgage of $366,000.00 amortized over 25 years. Interest for the first five years was 4.7% compounded semi-annually. a. Determine the Grewals' monthly...

Extracted text: The Grewals agreed to monthly payments on a mortgage of $366,000.00 amortized over 25 years. Interest for the first five years was 4.7% compounded semi-annually. a. Determine the Grewals' monthly payments. b. Determine the balance owing after the 5-year term. c. Before renewing for another term of 5 years at 5.4% compounded semiannually, the Grewals make an additional payment of $20,000. If they keep the same monthly payments, by how much will the amortization period be shortened?