Avicorp has a $15.5 million debt issue outstanding with a 6.3% coupon rate. The debt has semi-annual coupons, the next coupon is due in six months, and the debt matures in five years. It is currently priced at 92% of par value.

a.) What is Avicorp's pre-tax cost of debt? Note: Compute the effective annual return.

b.) If Avicorp faces a 40% tax rate, what is its after-tax cost of debt?

**I need help calculating Yield to Maturity given:

which is:

\($920 = ($31.50/(1+YTM)) + ($31.50/(1+YTM)^2)) + ($31.50/(1+YTM)^3)) + ($31.50/(1+YTM)^4) + ($31.50/(1+YTM)^5)) + ($31.50/(1+YTM)^6)) + ($31.50/(1+YTM)^7) + ($31.50/(1+YTM)^8)) + ($31.50/(1+YTM)^9)) + ($31.50/(1+YTM)^10)\)