finance question

mirons masterpieces has a bond outstanding with a coupon rate or $4\mathrm{.}6$ percent and semiannual payments. the bond currently sells for $$1028$ and matures in $18$ years. the par value is $$1000$ and the company's tax rate is $21$ percent. What is the company's annual after$-$tax cost of debt? Answer in percentages, two decimal places. Thank you very much!