If $A=\{1,2,3,4\}, B=\{3,4,5,6\}, C=\{5,6,7,8\}$ and $D=\{7,8,9,10\} ;$ find
$B \cup C \cup D$
If $A$ and $B$ are any two sets, then $A \cap (A \cup B)$ is equal to
Find the union of each of the following pairs of sets :
$A=\{a, e, i, o, u\} B=\{a, b, c\}$
The shaded region in the given figure is
If ${N_a} = \{ an:n \in N\} ,$ then ${N_3} \cap {N_4} = $