If sets $A$ and $B$ are defined as follows:
$A = \{(x, y) : y = \frac{1}{x}, 0 \neq x \in R\}$
$B = \{(x, y) : y = -x, x \in R\}$,then

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

If $A = \{1, 2, 3\}$ and $B = \{3, 8\}$,then find $(A \cup B) \times (A \cap B)$.

If $A$ and $B$ are not disjoint sets,then $n(A \cup B)$ is equal to

The shaded region in the given figure is

If $X = \{ 4^n - 3n - 1 : n \in N \}$ and $Y = \{ 9(n - 1) : n \in N \}$,then $X \cup Y = \dots$