If $n(U)$ = $600$ , $n(A)$ = $100$ , $n(B)$ = $200$ and $n(A \cap  B )$ = $50$, then $n(\bar A  \cap \bar B )$ is 

($U$ is universal set and $A$ and $B$ are subsets of $U$)

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

$A=\{a, b, c\}$

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 $\} $

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

${{\mathop{\rm U}\nolimits} ^\prime } \cap A =  \ldots $

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