A loan is being repaid with 60 monthly payments of $1000 each. At the time of the 20th payment, the borrower wishes to pay an extra $10,000 and then repay the new outstanding balance over the following 2 years with a revised monthly payment. The nominal annual rate of interest of 10% convertible monthly is the rate for both parts of this loan. Find the following. (a) The original loan amount. (b) The balance after the 20th payment. (c) The amount of the revised monthly payment.