If $A = \{1, 2, 4\}, B = \{2, 4, 5\}, C = \{2, 5\},$ then find $(A - B) \times (B - C)$.

Find the union of each of the following pairs of sets:
$A = \{a, e, i, o, u\}$,$B = \{a, b, c\}$

If $A = \{3, 6, 9, 12, 15, 18, 21\}, B = \{4, 8, 12, 16, 20\}, C = \{2, 4, 6, 8, 10, 12, 14, 16\}, D = \{5, 10, 15, 20\};$ find $B - D$.

If $A$ and $B$ are any two events of a sample space,then the set-theoretic description for the event: "Exactly one of the events $A, B$ occurs" is
(Here $E^c$ denotes the complement of the event $E$)

If $A$ and $B$ are two sets,then $A \cap (B - A)$ is equal to:

If $A$ and $B$ are two non-empty sets,then $(A - B) \cup (B - A)$ is equal to: