Problem $16-8($Algo$)$ Effect of bond rating change $[$LO $16-2]$

The yield to maturity for $10-$year bonds is as follows for four different bond rating categories. Use A ppendix $B$ and A ppendix. $D$ for an approximate answer but calculate your final answer using the formula and financlal calculator methods.

$\backslash$table$[[,],[$Alaa$,8\mathrm{.}4B\%$