Three charges are placed on a line: q$\_\{1\}=1\mathrm{.}6$mu$*$C at x$\_\{1\}=-1\mathrm{.}8$ cm$,$ q$\_\{2\}=3\mathrm{.}5$C at x$\_\{2\}=4\mathrm{.}3$cm and q$\_\{3\}=-2\mathrm{.}1$C at x$\_\{3\}=9\mathrm{.}5$ cm$.$ Determine the electric field at the origin of the coordinate system. $($include units with answer$)$