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}) = $

Let $U=\{1,2,3,4,5,6,7,8,9\}, A=\{1,2,3,4\}, B=\{2,4,6,8\}$ and $C=\{3,4,5,6\} .$ Find

$B^{\prime}$

If $U=\{a, b, c, d, e, f, g, h\},$ find the complements of the following sets:

$D=\{f, g, h, a\}$

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

$\{ x:x$ is a positive multiple of $3\} $

If $A$ is any set, then

Draw appropriate Venn diagram for each of the following:

$A^{\prime} \cap B^{\prime}$