Answer:
Driving in a straight line at 60 miles per hour
Step-by-step explanation:
In the first case there's an acceleration that modifies the direction of the movement.
In the second case there's a lineal acceleration that increases the speed of the car.
in the third case there's a negative acceleration that reduces the speed of the car.
On the third case the speed is constant so the acceleration is 0 mi/s^2