Rinck Import has several bond issues outstanding, each making semiannual interest payments. The bonds are listed below. If the corporate tax rate is 34 %, what is the after-tax cost of the company's market-value debt? (Answer is supposed to be 4.69%)

Bond 1: Coupon rate 7.5%; Price Quote 105.0; Maturity 5 years; Face Value $20,000,000

Bond 2: Coupon rate 5.8%; Price Quote 95.4; Maturity 8 years; Face Value $40,000,000

Bond 3: Coupon rate 7.7%; Price Quote 103.8; Maturity 151.5 years; Face Value $45,000,000

Bond 4: Coupon rate 8.1%; Price Quote 105.7; Maturity 25 years; Face Value $60,000,000