Answer and Explanation:
1. Revenge is a feeling created out of a grotesque and disadvantageous situation. This fits Ximbardo's argument about why good people do bad things, because he said that it is grotesque and environmentally bad situations that promote the evil of human beings. So we can conclude that revenge is the result of an evil and disadvantageous environment that makes good people want to cause harm to other people who have hurt them in some way.
2. These two texts can contribute to Zimbardo's research, as they reinforce the idea that something must happen in order for human evil to be expressed. In addition, they reinforce the idea that the human being is evil by nature, but they need a trigger for this evil to be "justified".