$1.$ In an x$-$y coordinate system you have three masses located as follows: m$=4\mathrm{.}0$kg at $(2\mathrm{.}0$m$,0),$ m$2=8\mathrm{.}0$kg at $(2\mathrm{.}0$m$,6\mathrm{.}0$m$)$ and m$3=5\mathrm{.}0$kg at $(-1\mathrm{.}0$m$,4\mathrm{.}0$m$).$ Where is the center$-$ of$-$mass $($Xcm$,$ Yem$)$ located?