The domain of the function $f(x) = \sqrt{2 - x} - \frac{1}{\sqrt{9 - x^2}}$ is:

Which of the following statements is false for the sets $A, B$ and $C,$ where
$A = \{x \mid x \text{ is a letter of the word } 'BOWL'\}$
$B = \{x \mid x \text{ is a letter of the word } 'ELBOW'\}$
$C = \{x \mid x \text{ is a letter of the word } 'BELLOW'\}$

Which of the following sets is infinite?

If $A = \{a, b\}$,$B = \{c, d\}$,$C = \{d, e\}$,then the set $\{(a, c), (a, d), (a, e), (b, c), (b, d), (b, e)\}$ is equal to:

Let $A = \{x : x \in N \text{ and } x \text{ is a multiple of } 2\}$,$B = \{x : x \in N \text{ and } x \text{ is a multiple of } 5\}$,and $C = \{x : x \in N \text{ and } x \text{ is a multiple of } 10\}$. Describe the set $(A \cap B) \cap C$.

If $n(U) = 600$,$n(A) = 100$,$n(B) = 200$,and $n(A \cap B) = 50$,then $n(\bar{A} \cap \bar{B})$ is (where $U$ is the universal set and $A$ and $B$ are subsets of $U$).