Answer:
If x represents time, the average rate of change of the function f(x) in the first three seconds is 40.
Explanation:
We know that the average rate of change which is also know as a slope of a function from x=a to x=b is calculated by the formula:

Here we are asked to find the average rate of change between x=0 to x=3 ( i.e. in the first three seconds)
It is calculated as follows:
