Answer:
The average rate of change is 3.375 times as fast.
Explanation:
The given function is

The average rate of change of a function f(x) is given by

Thus, average rate of change between Years 3 and 6 is given by

Now, average rate of change between Years 0 and 3

The ratio of these average rate of change is given by

Therefore, the average rate of change is 3.375 times as fast.