Answer: The average speed would be between 58.33 mph and 63.63 mph.
Explanation:
Since we have given that
Number of hours = 5.5
Distance of trip = 350 miles
So, Average speed would be

Number of hours = 6
Distance of trip = 350 miles
So, Average speed would be

So, the average speed would be between 58.33 mph and 63.63 mph.