Given Principal: $13,500, 6%, 240 days Partial payments: On 100th day, $5,200 On 180th day, $3,100

a. Use the U.S. Rule to solve for total interest cost. (Use 360 days a year. Do not round intermediate calculations. Round your answerto the nearest cent.)

b.Use the U.S. Rule to solve for principal balances. On the 100th day after the payment, and then on the 180th day after the payment. (Use 360 days a year. Do not round intermediate calculations. Round your answers to the nearest cent.)

c. Use the U.S. Rule to solve for final payment. (Use 360 days a year. Do not round intermediate calculations. Round your answerto the nearest cent.)