A firm offers terms of 2.8/7, net 60.

a. What effective annual interest rate does the firm earn when a customer does not take the discount? (Use 365 days a year. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)

b. What effective annual interest rate does the firm earn if the terms are changed to 3.8/7, net 60, and the customer does not take the discount? (Use 365 days a year. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)

c. What effective annual interest rate does the firm earn if the terms are changed to 2.8/7, net 90, and the customer does not take the discount? (Use 365 days a year. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)

d. What effective annual interest rate does the firm earn if the terms are changed to 2.8/12, net 60, and the customer does not take the discount? (Use 365 days a year. Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)