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

In a certain office,$72 \%$ of the workers prefer cold drink and $44 \%$ prefer tea. If each of them prefers cold drink or tea and $40$ like both,then the total number of workers in the office is

Let $A = \{1, 3, 5\}$ and $B = \{x : x \text{ is an odd natural number } < 6\}$. Which of the following is false?

If $A, B$ and $C$ are three sets such that $A \cap B = A \cap C$ and $A \cup B = A \cup C$,then:

Let $f:R \to R$ be defined by $f(x) = 2x + |x|$,then $f(2x) + f(-x) - f(x) = $

Which of the following pairs of sets are disjoint?
$(i)$ ${1, 2, 3, 4}$ and ${x : x in mathbb{N}, 4 \leq x \leq 6}$
$(ii)$ ${a, e, i, o, u}$ and ${c, d, e, f}$
$(iii)$ ${x : x \text{ is an even integer}}$ and ${x : x \text{ is an odd integer}}$