If a car is accelerating downhill under a net force 3674 N , what additional force would cause the car to have a constant velocity

For the car to move with constant velocity the additional force required is  

Explanation:

From the question we are told that

  The net force of the car is  

Generally the total  force acting on the  car is the net force plus the force due to gravity acting in direction of the car (Let denote it as )

So the total force acting on the car is mathematically represented as

Here this F representing the total force can be mathematically represented as

Now for constant velocity to be attained, the acceleration of the car will be zero  

So  at constant velocity

=>    

So  

=>  

=>