A firm offers terms of 2/15, net 60 . 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., 32.1 b. What effective annual interest rate does the firm earn if the discount is changed to 3 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 80 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 20 days? Note: Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16