Vehicle A which is $4000\mathrm{.}0$ kg runs a red light and enters an intersection while travelling at $81\mathrm{.}0$ km$/$h $[$E$].$ It collides with Vehicle B which is $(1)/(2)$ the mass of Vehicle A$.$ Vehicle B was travelling at $5\mathrm{.}00$ km$/$h $[$W$70$oN$].$ Soon after the collision Vehicle A was moving at $60\mathrm{.}0$ km$/$h $[$E$60$^oN$].$ Determine the velocity vector of Vehicle B immediately after the collision.