$5$ years ago, Barton Industries issued $25-$year noncallable, semiannual bonds with a $$1,000$ face value and a $6\%$ coupon, semiannual payment $($$$30$ payment every $6$ months$).$ The bonds currently sell for $$822\mathrm{.}87.$ If the firm's marginal tax rate is $25\%,$ what is the firm's after$-$tax cost of debt? Do not round intermediate calculations. Round your answer to two decimal places.