Notable Nothings plans to issue new bonds with the same yield as its existing bonds. The existing bonds have a coupon rate of interest equal to $5\mathrm{.}6\%($semiannual interest payments$),12$ years remaining until maturity, and a $$1,000$ maturity value; they are currently selling for $$918$ each.

a$.$ If Notable issues new bonds today, what will be its before$-$tax cost of debt?

b$.$ What will be its before$-$tax cost of debt if the price of its existing bonds is $$730$ when Notable issues the new bonds?