What do the differences between the points (as shown on the graph) represent?

Answer:
They represent the rise and run of the graph.
Step-by-step explanation:
The difference between the x-axis of the points represents the "run" of the graph (or how much you should run along x-axis to get to the next point.)
The difference between the y-axis of of the points represents the "rise" of the graph (or how much you should rise up the y-xis to get to the next point).
The ratio of rise to run is the slope of the graph, which tells us how many steps should we take on the y-axis for every step we move forward on the x-axis.
Answer:
c.
7 over 2 can be used to find the unit rate if one divides 7 by 2 and compares the result to 1.
hope this helped
p.s this is for edge