Let $n(U) = 700,\,n(A) = 200,\,n(B) = 300$ and $n(A \cap B) = 100,$ then $n({A^c} \cap {B^c}) = $

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

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

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

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

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

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

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

$\left(A^{\prime}\right)^{\prime}$

Which of the following statement is false (where $A$ $\&$ $B$ are two non empty sets)