(IN EXCEL) Consider the following mortgage Pass-through security generated with 15 year mortgages: Original balance: $ 435,000,000 Pass-through rate 5.35% WAC: 5.85% WAM: 180 months Prepayment Speed 185 PSA Generate an amortization schedule for this security and answer the following questions: a. What is the monthly mortgage payment? b. What is the maturity of the mortgage security with a PSA of 185? c. What is the maturity of the mortgage security with a PSA of 210? d. What is the balance in month 107 if prepayments slow to 85 PSA?