Design Speed:
Design speed is the maximum safe speed that can be maintained over a specific section of a roadway under favorable weather conditions, considering the design of the road and its alignment. It is a key parameter in the design of highways and other transportation infrastructure.

Stopping Distance:
Stopping distance is the total distance covered by a vehicle from the moment the driver applies the brakes until the vehicle comes to a complete stop. It consists of two components: the perception-reaction distance and the braking distance.

Perception-Reaction Distance:
Perception-reaction distance is the distance traveled by a vehicle from the moment the driver perceives a hazard and decides to apply the brakes until the brakes are actually applied. It includes the time taken by the driver to recognize the need to stop and physically react by applying the brakes.

Braking Distance:
Braking distance is the distance covered by a vehicle while the brakes are applied and the vehicle decelerates to a complete stop. It depends on various factors such as the vehicle's speed, weight, condition of the brakes, and the coefficient of friction between the tires and the road surface.

Calculating the Absolute Minimum Stopping Distance:
To calculate the absolute minimum stopping distance of a moving vehicle, we need to consider the vehicle's design speed and the maximum allowable deceleration.

1. Determine the Maximum Allowable Deceleration:
- The maximum allowable deceleration is typically specified by transportation authorities and depends on various factors such as road conditions, vehicle characteristics, and safety standards.
- Let's assume the maximum allowable deceleration is 4 m/s² (meters per second squared).

2. Convert the Design Speed to meters per second:
- Design speed is given in kilometers per hour (km/h), so we need to convert it to meters per second (m/s) for consistency.
- 80 km/h is equal to 22.22 m/s (rounded to two decimal places).

3. Calculate the Perception-Reaction Distance:
- The perception-reaction distance can be estimated using empirical formulas, which take into account the driver's reaction time and the vehicle's speed.
- Let's assume a perception-reaction time of 2 seconds.
- The perception-reaction distance can be calculated using the formula: Perception-Reaction Distance = Speed x Reaction Time.
- In this case, the perception-reaction distance is 22.22 m/s x 2 s = 44.44 meters.

4. Calculate the Braking Distance:
- The braking distance can be calculated using the formula: Braking Distance = (Speed²) / (2 x Deceleration).
- In this case, the braking distance is (22.22 m/s)² / (2 x 4 m/s²) = 61.69 meters.

5. Calculate the Absolute Minimum Stopping Distance:
- The absolute minimum stopping distance is the sum of the perception-reaction distance and the braking distance.
- In this case, the absolute minimum stopping distance is 44.44 meters + 61.69 meters = 106.13 meters.

Therefore, for a design speed of 80 km/h, the absolute minimum stopping distance of a moving vehicle should be approximately 106.13 meters.