Consider the following.

a$.$ What is the duration of a four$-$year Treasury bond with a $10\mathrm{.}5$ percent semiannual coupon selling at par?

b$.$ What is the duration of a three$-$year Treasury bond with a $10\mathrm{.}5$ percent semiannual coupon selling at par?

c$.$ What is the duration of a two$-$year Treasury bond with a $10\mathrm{.}5$ percent semiannual coupon selling at par?

Note: For all requirements, do not round intermediate calculations. Round your answers to $2$ decimal places $($e$.$g$.,32\mathrm{.}16).$ Use $$1,000$ as the face value.

$\backslash$table$[[$a$.$ Duration of the bond,,years$],[$b$.$ Duration of the bond,,years$],[$c$.$ Duration of the bond,,years$]]$