Toko Inc.$\text{'}$s bonds currently sell for $$780$ and have a par value of $$1,000.$ They pay a $$56$ annual coupon and have a $6-$yearmaturity, but they can be called in $6$ years at $$1,150.$ What is their yield to maturity $($YTM$)?$

a$.8\mathrm{.}31\%$

b$.6\mathrm{.}66\%$

c$.10\mathrm{.}77\%$

d$.9\mathrm{.}02\%$

e$.7\mathrm{.}38\%$