The total distance traveled by the vehicle is given as 595 km.
The total time taken by the vehicle is given as 8.5 hours.
We can use the formula for average speed, which is total distance traveled / total time taken, to find the average speed of the vehicle. Plugging in the values given in the problem, we get average speed = 595 km / 8.5 hours.
Solving for average speed, we get average speed = 70 km/hr.
Therefore, the average speed of the vehicle is 70 km/hr