1. Convert Units:

* Velocity: 80 km/h needs to be converted to meters per second (m/s).

* 1 km = 1000 m

* 1 hour = 3600 seconds

* 80 km/h * (1000 m/km) * (1 h/3600 s) = 22.22 m/s (approximately)

2. Understand the Concepts:

* Acceleration: Acceleration is the rate of change of velocity over time. It is measured in meters per second squared (m/s²).

* Final Velocity: The vehicle comes to a "dead stop", meaning its final velocity (v_f) is 0 m/s.

* Initial Velocity: The initial velocity (v_i) is 22.22 m/s.

3. Apply the Formula:

The formula for acceleration is:

acceleration (a) = (final velocity (v_f) - initial velocity (v_i)) / time (t)

4. Calculate:

a = (0 m/s - 22.22 m/s) / 13 s

a = -1.71 m/s² (approximately)

Answer:

The acceleration of the vehicle is approximately -1.71 m/s². The negative sign indicates that the vehicle is decelerating (slowing down).