5.15. If an amount a is borrowed at interest rate r for n years, then the total amount to be repaicd is given by Yearly payments of p each would reduce this amount bv 0 The loan will be repaid when these two quantities are equal a) For a loan of a = $100,000 and yearly pay ments of p $10,000, how long will it take to pay off the loan if the interest rate is 6 percent, i.e., r 0.06? (b) For a loan of a = $100,000 and yearly pay- ments of p- $10,000, what interest rate r would be required for the loan to be paid off in n - 20 years? (c) For a loan of a - $100,000, how large must the yearly l'ayments p be for the loan to be paid off in n - 20 years at 6 percent interest? You may use any method you like to solve the given equation in each case. For the purpose of this problem, we will treat n as a continuous vari able (i.e., it can have fractional values)