Gatsby chapter 3 questions

I just read Chapter 3 of The Great Gatsby, and here is what I got out of it. The girls were talking about a dress and suddenly brought up Gatsby and mentioned a rumor how somebody thought he killed a man once and how he was a German spy during the war and how he did not go to oggsford college. I think Gatsby is so mysterious because he doesn't want no trouble with anybody or he has a sketchy/scary look to him.Nick calls the man in the library a regular belasco. Nick imagined Gatsby to look florid,corpulent, and middle-aged.Nick found out that Jordan is incurably dishonest and cheated in her tournament.Both Jordan and nick had made a plan to go on a hydroplane the next day. at the end of this chapter, we learn that Nick's cardinal virtue is,"I am one of the few honest people that I have ever known. I think he mentions this at this point of the book because after all the people he had talked to he realized they have lied about what they said/do.