Just need c-e answered. thank you!

Chuck Boyl saw the following advertisement for a used Volkswagen Bug and decided to work out the numbers to be sure the ad had no errors. Cash price $7,970 Down payment $0 Annual percentage rate 12.78% Deferred price $10,879.20 or 60 payments at $181.32 per month a. Calculate the amount financed, Answer is complete and correct. Amount financed $ 7,970 b. Calculate the finance charge. (Do not round intermediate calculations. Round your answer to the nearest cent.) Answer is complete and correct. Finance charge $ 2,909 20 c. Calculate the APR by formula. (Do not round intermediate calculations. Enter your answer as a percentage rounded to 1 decimal place.) Answer is complete but not entirely correct. APR by formula 7.3 X % Help Check my work mode : This shows what is correct or incorrect for the work you have completed so far. It does not indicate compl c. Calculate the APR by formula. (Do not round intermediate calculations. Enter your answer as a percentage rounded to 1 decimal place.) Answer is complete but not entirely correct. APR by formula 7.3 % d. Calculate the monthly payment by add-on-method. (Do not round intermediate calculations. Round your answer to the nearest cent.) Answer is complete but not entirely correct. Monthly payment by add-on-method 66.18 e. Calculate the monthly payment by formula. (Do not round intermediate calculations. Round your answer to the nearest cent.) Answer is complete but not entirely correct. Monthly payment by formula $ 66.18