Find the union of each of the following pairs of sets :
$A = \{ x:x$ is a natural number and $1\, < \,x\, \le \,6\} $
$B = \{ x:x$ is a natural number and $6\, < \,x\, < \,10\} $
If ${N_a} = [an:n \in N\} ,$ then ${N_5} \cap {N_7} = $
State whether each of the following statement is true or false. Justify you answer.
$\{2,6,10,14\}$ and $\{3,7,11,15\}$ are disjoint sets.
If $A$ and $B$ are disjoint, then $n(A \cup B)$ is equal to
If $A \cap B = B$, then