Question

Null set should written in list form nd set builder form

Answer 1

A set which has no element is called Null Set.
So,
{x:x∈N,x≠x}=ϕ
Clearly, No natural number can be different from itself.
So, The set of all those natural numbers, each of which is not equal to itself, is an null set.

Null set in list form=Φ