If $A=\{3, 5, 7, 9, 11\}, B=\{7, 9, 11, 13\}, C=\{11, 13, 15\}$ and $D=\{15, 17\}$,find $A \cap (B \cup C)$.

Let $A = \{ \theta : 2\cos^2 \theta + \sin \theta \le 2 \}$ and $B = \{ \theta : \frac{\pi}{2} \le \theta \le \frac{3\pi}{2} \}$,then $A \cap B$ is

If $X = \{a, b, c, d\}$ and $Y = \{f, b, d, g\},$ find $Y - X$.

If $A = \{1, 2, 3, 4, 5\}, B = \{2, 4, 6\}, C = \{3, 4, 6\},$ then $(A \cup B) \cap C$ is

If ${N_a} = \{an : n \in N\}$,then the set ${N_6} \cap {N_8} = $

Let $X$ be a non-empty set and let $P(X)$ denote the collection of all subsets of $X$. Define $f: X \times P(X) \rightarrow R$ by $f(x, A) = \begin{cases} 1, & \text{if } x \in A \\ 0, & \text{if } x \notin A \end{cases}$. Then,$f(x, A \cup B)$ equals