Please provide the approximation formula for A-E. Thank you

Cost of debt using the approximation formula For each of the following $1,000-par-value bonds, assuming annual interest payment and a 40% tax rate, calculate the after-tax cost to maturity using the approximation formula. Bond Life 20 years 16 15 25 22 B Discount (-) or premium (+) - $20 10 - 15 Underwriting fee $25 40 30 15 20 Coupon interest rate 9% 10 12 9 11 D par E -60