Answer: Choice A. 4 times
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Explanation:
We'll be using this formula
to compute the average rate of change (AROC) from x = a to x = b. Note how this is effectively the slope formula because y = f(x).
To start things off, we'll compute the AROC from x = 1 to x = 2.
Do the same for the AROC from x = 3 to x = 4.
The jump from m = 10 to m = 40 is "times 4", which is why choice A is the final answer.