Suppose a U$.$S$.$ treasury bond will pay $$1,000$ seven years from now. If the going interest rate on $7-$year treasury bonds is $4\mathrm{.}55\%,$ how much is the bond worth today?

a$.$ $$729\mathrm{.}84$

b$.$ $$732\mathrm{.}37$

c$.$ $$700\mathrm{.}50$

d$.$ $$721\mathrm{.}82$

e$.$ $$765\mathrm{.}69$