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

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

If $A, B$ and $C$ are any three sets,then $A - (B \cap C)$ is equal to

If $A = \{x : f(x) = 0\}$ and $B = \{x : g(x) = 0\}$,then $A \cap B$ will be

For any two independent events $E_1$ and $E_2$,$P\{(E_1 \cup E_2) \cap (\bar{E}_1 \cap \bar{E}_2)\}$ is

In a school,there are three types of games to be played. Some students play two types of games,but none play all three games. Which Venn diagram$(s)$ can justify the above statement?