A one$-$turn wire loop has a radius of $22$ cm and carries a current of $5\mathrm{.}0$ A $.$ Calculate $B$ at its center.

$($a$)1\mathrm{.}4{10}^{-5}T$

$($b$)7\mathrm{.}2{10}^{-2}T$

$($c$)6\mathrm{.}9{10}^{-6}T$

$($d$)9\mathrm{.}9{10}^{-5}T$

$($e$)3\mathrm{.}5{10}^{-4}T$