A $2\mathrm{.}0-$kgkg cart collides with a $1\mathrm{.}0-$kgkg cart that is initially at rest on a low$-$friction track. After the collision, the $1\mathrm{.}0-$kgkg cart moves to the right at $0\mathrm{.}50$ m$/$sm$/$s and the $2\mathrm{.}0-$kgkg cart moves to the right at $0\mathrm{.}30$ m$/$sm$/$s $.$