Mechanics

I’m stuck on a few qs and I donno how I’m meant to go abouts them. Any help appreciated.
A lorry of 5 tonnes is about to tow a car of mass 1 tonne. Initially the two rope is slack and the car stationary. As the rope becomes taut the lorry is travelling at 2m/s. Find the speed of the car once it is being towed .

The question is not entirely clear, but I assume that it's a conseration of momentum question.

Yh that’s what I thought but I donno how to set it up

So do I do when the rope is slack and when the rope is taut cos I’m not sure of the velocities either way

Initially you have 5 tonnes travelling at 2m/s. After that you have 5+1 tonnes. What speed does that travel, assuming that momentum is conserved?