Answer:
The average rate of change of a linear function is the slope of the line. Since we are given the following coordinates:
(0,150) and (3,0)
We can easily solve for the slope.
m = (y2 - y1) / (x2 - x1)
m = (0 - 150) / (3 - 0) = -50
Therefore, the average rate of change of the function in the three seconds is -50.