Question

what is the correct title for the graph for the experiment of how many drops of water can fit onto a penny dipped in soap vs a not dipped in soap?
the number of drops of water
the penny dipped in soap or not
penny vs drops of water

Explanation:

The experiment compares the number of water - drops on a penny dipped in soap and not dipped in soap. A good graph title should clearly show the two variables being compared. "Penny vs drops of water" is too general. "The number of drops of water" doesn't mention the soap condition. "The penny dipped in soap or not" doesn't mention the number of drops. The best title is one that shows the comparison of the two key elements: the state of the penny (dipped in soap or not) and the number of drops of water.

Answer:

Penny vs drops of water