If $A=\{3,5,7,9,11\}, B=\{7,9,11,13\}, C=\{11,13,15\}$ and $D=\{15,17\} ;$ find

$\left( {A \cup D} \right) \cap \left( {B \cup C} \right)$

If $A=\{x \in R:|x|<2\}$ and $B=\{x \in R:|x-2| \geq 3\}$ then

Find the union of each of the following pairs of sets :

$A=\{1,2,3\}, B=\varnothing$

If $A = \{ x:x$ is a natural number $\} ,B = \{ x:x$ is an even natural number $\} $ $C = \{ x:x$ is an odd natural number $\} $ and $D = \{ x:x$ is a prime number $\} ,$ find

$C \cap D$

If $\mathrm{R}$ is the set of real numbers and $\mathrm{Q}$ is the set of rational numbers, then what is $\mathrm{R - Q} ?$

Find the union of each of the following pairs of sets :

$A=\{1,2,3\}, B=\varnothing$