Let $A = \{1, 2, 3, 4, 5, 6\}$. Insert the appropriate symbol $\in$ or $\notin$ in the blank space:
$5 \dots A$

If $A = \{1, 2, 3, 4, 5, 6\}$, then which of the following statements is not true?

Let $A$ and $B$ be two non-empty subsets of a set $X$ such that $A$ is not a subset of $B$. Then:

An alternative equivalent circuit for the circuit is

For two sets $A$ and $B$,$A \cup B = A$ if and only if

In each of the following,determine whether the statement is true or false. If it is true,prove it. If it is false,give a counterexample.
If $A \subset B$ and $B \in C,$ then $A \in C$.