Each second, $1\mathrm{.}25{10}^{19}$ electrons in a narrow beam pass through a small hole in a wall. The beam is perpendicular to the wall. Using Ampere's law, determine the magnitude of the magnetic field in the wall at a radius of $0\mathrm{.}750$ m from the center of the beam.

A$)1\mathrm{.}18{10}^{-9}T$

B$)5\mathrm{.}34{10}^{-7}T$

C$)2\mathrm{.}62{10}^{-3}T$

D$)4\mathrm{.}14{10}^{8}T$

E$)3\mathrm{.}33{10}^{12}T$