Please help I am taking an final right nowSolutionAnswer a F

Please help I am taking an final right now:

Answer a.

Face Value = $1,000
Current Price = $900
Annual Coupon = $86
Time to Maturity = 20 years

Let annual interest rate be i%

$900 = $86 * PVIFA(i%, 20) + $1,000 * PVIF(i%, 20)

Using financial calculator:
N = 20
PV = -900
PMT = 86
FV = 1000

I = 9.76%

So, yield on new issue of bonds is 9.76%

Answer b.

Before-tax Cost of Debt = 9.76%

After-tax Cost of Debt = 9.76% * (1 - 0.35)
After-tax Cost of Debt = 6.34%