$4\mathrm{.}89.$ Suppose you were offered a $12-$year, $15\%$ cou$-$

pon, $$1,000$ par value bond at a price of $$1,298\mathrm{.}68.$

What rate of interest $($yield to maturity$)$ would you

earn if you bought the bond and held it to maturity

$($at semiannual interest$)?$