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?( provide 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%?( provide answer as present round 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?( provide answer as a percent rounded to 2 decimal places)

d. What effective annual interest rate does the firm earn if the discount period is increased to 15 days?( provide answer as present round to 2 decimals)