Bond Yield and After$-$Tax Cost of Debt

A company's $8\%$ coupon rate, semiannual payment, $$1,000$ par value bond that matures in $20$ years sells at a price of $$645\mathrm{.}38.$ The company's federal$-$plus$-$state tax $30\%.$

What is the firm's after$-$tax component cost of debt for purposes of calculating the WACC? $($Hint: Base your answer on the nominal rate.$)$ Round your answer to two decimal places.

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