Answer:
Essentially, ethos is about believability. Will your audience find you believable? What can you do to ensure that they do? You can establish ethos or credibility in two basic ways. You can use or build your own credibility on a topic, or you can use credible sources, which in return builds your credibility as a writer
The police throw tear gas; The Hate U Give was one of my favorite books to read. :-)
For question 1 it's definitely D.Question 2. I'm pretty sure its D. (not positive)
Question 3. Not 100% sure