A firm offers terms of 1/10, net 40 . a. What effective annual interest rate does the firm earn when a customer does not take the discount? Note: 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 discount is changed to 2 percent? Note: 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 credit period is increased to 60 days? Note: 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 discount period is increased to 15 days? Note: Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16