1. Convert Units:

* Velocity: 100 km/h needs to be converted to meters per second (m/s).

* 1 km = 1000 m

* 1 hour = 3600 seconds

* 100 km/h * (1000 m/km) * (1 h/3600 s) ≈ 27.78 m/s

2. Determine the Change in Velocity:

* The vehicle starts at 27.78 m/s and comes to a dead stop (0 m/s).

* Change in velocity (Δv) = 0 m/s - 27.78 m/s = -27.78 m/s

3. Calculate Acceleration:

* Acceleration (a) is the change in velocity over time.

* a = Δv / Δt

* a = -27.78 m/s / 30 s

* a ≈ -0.93 m/s²

Important Note: The negative sign indicates that the acceleration is in the opposite direction of the initial velocity. This means the vehicle is *decelerating* or slowing down.

Therefore, the acceleration of the vehicle is approximately -0.93 m/s².