Greg Corp has a bond outstanding with $15$ years to maturity, an $9\%$ annual coupon rate, semiannual payments, and a $$1,000$ par value. The bond has a $6\%$ yield to maturity, but it can be called in $7$ years at a price of $$1,200.$ What is the bond's yield to call?

$3\mathrm{.}05\%$

$5\mathrm{.}55\%$

$4\mathrm{.}64\%$

$9\mathrm{.}27\%$

$2\mathrm{.}77\%$

$6\mathrm{.}11\%$