$($iii$)$ Debt capital

$($b$)$ Prescott Corporation issues a $$1,000$ par, $20-$year bond paying the market rate of $10\%.$ Coupons are annual. The bond will sell for par since it pays the market rate, but flotation costs amount to $$50$ per bond. What is the pre$-$tax and after$-$tax cost of debt for Prescott Corporation?