Hi guys,

Hopefully this is the right section, but I've got a question to with sets.

I've been given 4 separate sets that differentiate only a little and I was hoping someone could let me know how they are different?

A={a, b}

B={{a}, {b}}

C= {a, b, {a, b}}

D= {{a}. {b}. {b, a}}

To me they all look really similar but I just don't know how to explain the differences. So if someone could help me that would be awesome!

Thanks