The longer you are friends with someone, the more likely you are to discover differences between you. True False

true

Explanation:

As you are friends with someone for a long period of time you tend to learn things about each other that you new nothing about, and that includes the differences.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.