Answer:
25
Explanation:
On the graph, you can see the train has traveled from 0 to 150 miles (the Y-axis), and it did that in 6 hours (X-axis).
That means that it traveled 150 miles in 6 hours.
A speed is a distance divided by a time (like miles/hour). So, to get the speed, we need to divide the distance traveled by the time it took to do it:
S = 150 miles / 6 hours = 25 miles per hour