In another scenario (not related to part a or b), lets assume that you prefer the 10-year loan because you want to pay off the loan faster. Now the bank also offers a 10-year variable-interest mortgage loan with the first 3 years locked with an APR of 3%. And after 3 years, the bank will use floating interest rate based on market condition. Somehow you believe that the floating interest rate is going to be within range of 1% to 10%, with 4.5% being the most likely number. First, calculate the two separete amortization schedules for (a) first 3 years with fixed 3% APR; (b) the remaining 7 years with 4.5% APR. Next, conduct a sensitivity analysis of how your monthly payment (PMT) and total interest payment for these 10 years are going to differ across different assumptions of APR for the 7 years.\

After the first 3 years, we have:
APR =	4.50%
Yeas-to-Maturity	7
PV =	$ -	=ending balance at end of Y3
Compounding Periods per Year	12
PMT (quarterly)		= the monthly payment from Y4 to Y10
Year	Month	Beginning Balance	Total Payment	Interest Payment	Principal Payment	Ending Balance
4	37
4	38
4	39
4	40
4	41
4	42

Although the month as given in the above table extends to 117 (currently but I just need to know the excel formula.Filling these table will be enough.