When you plot the offered points on the graph, you find only one of them falls inside the shaded region:
... D. 43 pepperoni slices and 25 cheese slices
Is 16x47 what you're asking for? The answer to 16x47 is 752 if that's what you needed.
To find the average rate of change in a interval

We use the following formula:

Applying this to our interval

We have the following rate of change:

We have an average rate of change equals to 6.