A loan of $2000 is being repaid by equal monthly payments for an unspecified length of time. Interest on the loan is j2 = 15%. (Do not round intermediate calculations. Round your answers to 2 decimal places.) a) If the amount of principal in the 4th payment is $40, what amount of the 18th payment will be principal? Amount of principal in the 18th payment b) Determine the regular monthly payment. Regular monthly payment $ Check my work