Slope in the first second: 20 m/s
Slope in the next second: 40 m/s
Average slope: 30 m/s
Explanation:
On a distance-time graph, the slope of the curve represents the speed of the object.
In fact, we have:
- The distance covered is the change in the y-variable, so

- The time elapsed is the change in the x-variable, so

Speed is the ratio between distance and time, therefore

which corresponds to the slope of the line.
In this problem, we have a ball moving from 20 m to 40 m in 1 s, so


So the slope in the first second is

In the next second, the ball moves from 40 m to 80 m, so


So the slope in the next second is

While if we consider the overall graph in the 2 seconds, we have


So the average slope is

Learn more about speed:
brainly.com/question/8893949
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