A $3\mathrm{.}1-$kg $($m$1)$ object traveling at $5\mathrm{.}6$ m$/$s collides head$-$on with a $4\mathrm{.}3-$kg $($m$2)$ object traveling in the opposite direction at $4\mathrm{.}3$ m$/$s$.$ The collision is perfectly elastic.

a$)$ what is the final velocity of m$1?$

b$)$ What is final velocity of m$2?$

c$)$ What is the total kinetic energy after the collision?