HElP!!!! Discrete Math for CS C++ - Sets and Relations

I have few questions that i do not know how to answer it, can you give a short answer. (Please do not copy and paste on the internet)

Sets Use-

1)What is the purpose of learning the set rules/laws?

2)What do they represent to you?

Sets and classes -

3) How are sets, OOP classes and concepts related?

4) What are all the rules for sets? Create a list, with the symbols, alternative symbols, definition and example and Venn Diagram Illustrating each.