Given $n(U) = 20$, $n(A) = 12$, $n(B) = 9$, $n(A \cap B) = 4$, where $U$ is the universal set, $A$ and $B$ are subsets of $U$, then $n({(A \cup B)^C}) = $

Taking the set of natural numbers as the universal set, write down the complements of the following sets:

$\{ x:x$ is an even natural number $\} $

Taking the set of natural numbers as the universal set, write down the complements of the following sets:

$\{ x:x\, \ge \,7\} $

If $A$ and $B$ are two sets, then $A \cap (A \cup B)'$ is equal to

The shaded region in venn-diagram can be represented by which of the following ?

Let $\mathrm{U}$ be universal set of all the students of Class $\mathrm{XI}$ of a coeducational school and $\mathrm{A}$ be the set of all girls in Class $\mathrm{XI}$. Find $\mathrm{A}'.$