Nico Trading Corporation is considering issuing long$-$term debt. The debt would have a $30$ year maturity and a $10$ percent coupon rate. In order to sell the issue, the bonds must be underpriced at a discount of $5$ percent of face value. In addition, the firm would have to pay flotation costs of $5$ percent of face value. The firm's tax rate is $35$ percent. Given this information, the after tax cost of debt for Nico Trading would be $\_\_\_\_\_\_\_.$

The answer is $7\mathrm{.}26\%$ but how?