Question

If $S$ is any set, then the family of all the subsets of $S$ is called the power set of $S$ and it is denoted by $P\left(S\right)$. Power set of a given set is always non-empty. If $A$ has n elements, then $P\left(A\right)$ has ?

Answer 1

No .of subsets for a set of $n$ elements is $2^n$ so,

If $A$ has n elements, then $P\left(A\right)$ has $2^n$ elements.