Answer:
<h2>the car must move with the speed</h2><h2>

</h2>
Explanation:
As we know that the momentum of the car and truck is same
so as per the formula of momentum we have

so we have

so we will have


So the car must move with the speed

This question apparently comes after an EARLIER one,
where you were told either the voltage across the same
capacitor or the total charge stored in it. You can't answer
THIS one without that information.
What measures we can't answer without the measures