A long, hollow, cylindrical conductor $($inner radius $2\mathrm{.}8$ mm $,$ outer radius $5\mathrm{.}6$ mm $)$ carries a current of $57$ A distributed uniformly across its cross section A long thin wire that is coaxial with the cylinder carries a current of $55$ A in the opposite direction. What is the magnitude of the magnetic field $($a$)1\mathrm{.}3$ mm $,($b$)2\mathrm{.}8$ mm $,$ and $($c$)5\mathrm{.}8$ mm from the central axis of the wire and cylinder?

$($a$)$ Number

Units

$($b$)$ Number $$ Units $$

$($c$)$ Number $$ Units $$