In the figure below, a long circular pipe with outside radius $R=2\mathrm{.}07cm$ carries a $($uniformly distributed$)$ current $i=14\mathrm{.}9mA$ into the page. A wire runs parallel to the pipe at a distance of $3\mathrm{.}00$ R from center to center. Find the $($a$)$ magnitude and $($b$)$ direction $($into or out of the page$)$ of the current in the wire such that the ratio of the magnitude of the net magnetic field at point $P$ to the magnitude of the net magnetic field at the center of the pipe is $1\mathrm{.}72,$ but it has the opposite direction.

$($a$)$ Number

Units

$($b$)$