In rule method the null set is represented by

In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.

If $x \in A$ and $A \not\subset B$, then $x \in B$

Write the following intervals in set-builder form :

$\left( { - 3,0} \right)$

Which of the following sets are finite or infinite.

$\{1,2,3 \ldots .\}$

Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?

$\{ \{ 3,4\} \}  \subset A$

Examine whether the following statements are true or false :

$\{ x:x$ is an even natural number less than $6\}  \subset \{ x:x$ is a natural mumber which divide $36\} $