Using the diagram provided in the link, rank each of the given paths on the basis of the change in electric potential. Rank the largest-magnitude positive change (increase in electric potential) as largest and the largest-magnitude negative change (decrease in electric potential) as smallest.
So far I have c to d holding the highest potential since they are equivalent. Then b to a next since it is the closest to the positive charge. However I have no idea where to do from here and I have tried multiple rankings and none of them seem to work out.
Do any equations help in determining the ranking? How can I better understand how to derive the answer to this question?