Francine Fracking Inc. took out an $800,000 mortgage for a new warehouse. The monthly payments were set at $7500 with a nominal rate of 7.80% compounded semiannually.

a. What is the length of the amortization period, rounded to the next month if required?

b, If the interest rate changes to 9.48% compounded semiannually at the beginning of the fourth year, what monthly payment (rounded to the nearest dollar) is required in order to maintain the same overall amortization period.