A car travels 100 meters in 4.0 seconds. Find the average velocity

The velocity can't be found with the given information. Velocity includes

the direction of motion, and that's not mentioned in the question.

Average speed during the time =

(distance covered) / (time to cover the distance) =

(100 m) / (4.0 seconds) = 25 m/s.

If you mean in m/s (metres per second), then to work it out you do (distance traveled in metres) / (time taken in seconds) = velocity in metres per second

So inputting what we know

100/4 = Velocity in m/s

Velocity = 25m/s