Question $7($Mandatory$)(2$ points$)$

A toroid is made of $2000$ turns of wire of radius $2\mathrm{.}00$ cm formed into a donut shape of inner radius $10\mathrm{.}0$ cm and radius $14\mathrm{.}0$ cm $.$ When a $30\mathrm{.}0-$A current is present in the toroid, the magnetic field at a distance of $11\mathrm{.}0$ cm from th center of the toroid is

a$)0\mathrm{.}109$ T $.$

b$)0\mathrm{.}120$ T $.$

C$)0\mathrm{.}685$ T $.$

d$)0\mathrm{.}600$ T $.$

e$)0\mathrm{.}0857$ T $.$