Three charges are fixed to an xy coordinate system. A charge of $+27$ C is on the y axis at y $=+4\mathrm{.}1$ m$.$ A charge of $-13$ C is at the origin. Lastly, a charge of $+46$ C is on the x axis at x $=+4\mathrm{.}1$ m$.$

Determine:

 $($a$)$ the magnitude and

 $($b$)$ direction of the net electrostatic force on the charge at x $=+4\mathrm{.}1$ m$.$ Specify the direction as a positive angle relative to the $+$x axis.