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

- A
$A' \cap {\rm B}'$

- B
$A' \cup B'$

- C
$A \cap B$

- D
$A \cup B$

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

$\{x: x+5=8\}$

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

$C=\{a, c, e, g\}$

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

$\{ x:x$ is a prime number $\} $

Draw appropriate Venn diagram for each of the following:

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

Fill in the blanks to make each of the following a true statement :

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