A $21-$loop circular coil $18$ cm in diameter lies in the $xy$ plane. The current in each loop of the coil is $7\mathrm{.}2$ A clockwise, and an external magnetic field vec$(B)=(0\mathrm{.}9$hat$(i)+0\mathrm{.}35$hat$(j)-0\mathrm{.}9$hat$(k))T$ passes through the coil.

Part B

Determine the torque on the coil due to the external magnetic field in a component form. Express your answers in newton$-$meters separated by commas.

${}_x,{}_y,{}_z=$

$N*m$

Part C

Determine the potential energy $U$ of the coil in the field $($take $U=0$ at $=\frac{\text{I}}{2}).$

Express your answer in Joules.