Question

Describe the forces acting on a car as it moves along a level highway in still air at a constant speed.

Answer 1

Gravity pulls it down,
The ground pushes back,
Drag or air resistance inhibits forward motion,
Friction between the tires and the ground/road pulls the car forward (or backwards as the case may be,)

Forces that really don't count due to the way that your question is worded are:

The suspension system holds the car chassis up (but that is PART OF THE CAR so you can't count it,)
Force from the engine (also part of the car) turns the drive mechanism of the wheels

Answer 2

Thank you so much

Answer 3

you're welcome