This is a quote from "The Secret Life of Walter Mitty", and it is a made-up term. He is not a skilled surgeon, so he made up the term obstreosis (a word that does not even exist), duct is like a passage, the same way as tract. So this "disease" makes no sense and does not exist.
Answer:
it is an external conflict
Cassius wants Brutus to join the conspiracy because he knows that Brutus is an influential person and the people love him.
If they can get as many respectable people on their side, then the deed they have planned will seem acceptable to the people (or so they think).
Answer:
The teacher offered to show us how to parallel park; we decided to all Kuzco for hep instead.
