A GM and a Ford bond both have $4$ years to maturity, a $$1,000$ par value, a BB rating and pay interest semiannually. GM has a coupon rate of $6\mathrm{.}7\%,$ while Ford has a coupon rate of $5\%.$ The GM bond trades at $90\mathrm{.}55($percent of par$).$ What is the yield to maturity $($YTM$)?$