Answer:
Montresor decides to seek revenge against Fortuanato because he believes that Fortunato has insulted him. The story says "the thousand injuries of Fortunato I had borne as I best could, but when he ventured upon insult I vowed revenge." We are not told the specifics of this insult.
Explanation:
I am pretty sure it is using ethos :)
There is a quote that accurately portrays the mood when Helen discovers her husbands fate:
"Scout," said Dill, "She just fell down in the dirt. Just fell down in the dirt, like a giant with a big foot just came along and stepped on her. Just ump-" Dills fat foot hit the ground. "Like you'd step on an ant."
Helen was very upset about Toms death.