What new characters are introduced in chapter 2? Are they greasers or socs? How do
you know?

The new characters that are introduced are Cherry Valance and Marcia. They are socs because Ponyboy said that they are nice-looking girls and they are well dressed and that they weren't greasers. Ponyboy is a greaser, How you know this is that her and her friend called them greasers and all the socs call them grasers.

Explanation:

I have read the book.

the sentence that contains a restrictive clause is a.they decided to meet where the band was performing

explanation:

a restrictive clause is also known as an essential clause