10.you plan to purchase a $ 100,000 house using a 30- year mortgage obtained from your local credit union. the mortgage rate offered is 8.25 percent. a. calculate your monthly payments on this mortgage. b. create an excel file with 7 columns (months, payment, interest, principle, balance, %interest and %principle) for all 360 months. c. calculate the amount of interest paid over the life of this mortgage.