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

Which of the following is an empty set?

Given the sets $A = \{1, 3, 5\}$,$B = \{2, 4, 6\}$ and $C = \{0, 2, 4, 6, 8\}$,which of the following may be considered as a universal set for all the three sets $A$,$B$ and $C$?

Let $A, B$ and $C$ be three sets. If $A \in B$ and $B \subset C$,is it true that $A \subset C$? If not,give an example.

Consider the sets $\phi, A = \{1, 3\}, B = \{1, 5, 9\}, C = \{1, 3, 5, 7, 9\}$. Insert the symbol $\subset$ or $\not\subset$ between the pair of sets: $B \dots C$.

List all the elements of the following set:
$A = \{ x:x \text{ is an odd natural number} \}$