A 30-year loan of 62577.89 is to be repaid with annual payments at the end of each year according to the following schedule: . For the first 10 years the payments are 4128.8945 each . For the next 10 years, each payment is made of 3000 to the principal plus interest on the outstanding loan balance; . For the last 10 years, payments are arranged according to a sinking fund method where the sinking fund earns an effective rate of 4% per year. The effective annual interest rate on the loan is 5% for the first 20 years and 6% afterward. a) Find the principal repaid at the end of the 5th year. . b) Find the outstanding loan balance at the end of the 20th year. c) The amount X of the annual deposit into the sinking fund over the last ten year. d) The total amounts of interest paid during the first 10 years and during the last 20 years