Calculate the average speed between 0 s and 20 s

2 m/s

Step-by-step explanation:

Notice that the slope of the time period from 0s to 20s is linear.  This means we can simply look at the distance traveled over the amount of time.  So the distance and time both start at 0.  At 20s, the distance is 40m.

So we can say the following to find the slope:

(40m - 0m) / (20s - 0s) == 40m / 20s == 2 m/s

Hence, the average speed between 0s and 20s is 2m/s.

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