In official guide, ETS only defines the term "subset"?. I'm wondering:
1. if there is any distinction between "proper subset" and "subset" in GRE.
2. If A={1,2,3} and B={1,2,3,3}, can I say that A is a subset of B and that B is also a subset of A?
3. if A={1,2,3} and B is a set not shown. Can B={1,2,3} also? In that case can I say that A is a subset of B and that B is also a subset of A? (a weird question though)?
I appreciate your reponse.
fr