A firm offers terms of 3/7, net 30 . 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 4/7, net 30 , 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 3/7, net 45, 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 3/12, net 30 , 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.)