0
The set of people who answered this question before I did.
There is only one empty set (a consequence of the Axiom of Extensionality). So the above answer is correct, and is equal to every other example.
No, it is the empty set. Then the set containing only the number 0 (Peano's first axiom).
An axiom system is a set of axioms or axiom schemata from which theorems can be derived.
It's an axiom.
An empty set is not a proper subset of an empty set.An empty set is not a proper subset of an empty set.An empty set is not a proper subset of an empty set.An empty set is not a proper subset of an empty set.