Excel Spreadsheet Dynamic Model Example of a Simple Loan a. What is the effect of a change in the interest rate from 8% to 10% in the spreadsheet model shown in Figure 6.3? b. For the original model in Figure 6.3, what interest rate is required to decrease the monthly payments by 20% ? What change in the loan amount would have the same effect? c. In the spreadsheet shown in Figure 6.4, what is the effect of a prepayment of $200 per month? What pre-payment would be necessary to pay off the loan in 25 years instead of 30 years