Answer: 1.25 dollars per roll
Step-by-step explanation:
If the relationship is graphed with the number of rolls sold on the x-axis and the money earned on the y-axis
Then the two points on that line will be (14,17.50) and (16,20)
We know that the slope of a lien with points
is give by:-

Hence, the slope of the graph with points (14,17.50) and (16,20) is given by :-

Therefore, the slope of the graph = 1.25 dollars per roll.