The last description makes the most sense, as to how the wording "mob" and "populace" imply them as behaving as group. Called social group psychology, many people "join the crowd" when it comes to supporting or opposing certain events, causes, or acts.
I don't know for sure but I think the second one is an intensive pronoun
B) By flashing forward to show what happens in the future.
In chapter 26, when Scout tries to talk to Jem about Miss Gates she mentions the courthouse. Jem grabs Scout and tells her never to mention that courthouse to him again. Jem is still very upset about what happened to Tom Robinson. He believed that the jury would find Tom innocent because Atticus proved that he did not hurt Mayella. Jem's innocent outlook on life was stolen from him that day and he has yet to deal with it emotionally. Atticus tells Scout, "don't let Jem get you down."
