During the presidential election, Vernon tends to focus only on the news reports that support his view that one candidate is better than the other. He doesn't read any articles that have a headline casting doubts on his preferred candidate. Vernon is demonstrating the bias.

Confirmation

Explanation:

Confirmation bias is the mechanism in which a person tends to rely and search for the evidence that strengthen and favor their already existing beliefs .They tend to ignore other non-favoring sources and facts on their existing theories.

According to the question,Vernon is displaying confirmation bias because he is focusing and considering the news and reports that supports his preferred candidates and ignores other articles supporting other candidates.

the factors that the economies of the muslim empires prosper were:

1- land trade routes-located between three continents  

2- sea trade routes

trade contributed to the spread of muslim empires, and with that islamic culture led to a growing feeling of internationalism resulted in the transfer of technology, science, and other cultural forms.