Gordon Barbara wishes to purchase a mansion in Gotham City. To do so, she will have to borrow 12 million dollars. The market interest rate is 0.50% per month.

a) Suppose Gordon takes a 30-year loan with equal monthly payments. What will be the amount of the monthly payments?

b) Suppose instead, Gordon takes a 90-year loan with equal monthly payments. What will be the amount of the monthly payments?

c) Now suppose that Gordon takes a 90-year loan with equal monthly payments, as in (b). Further, suppose that 30 years from now, market interest rates drop to 0.25% per month. Gordon decides to refinance and takes out a 60-year loan. What will be the amount of the new payments?