Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 5\, .......\, A$
Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:
$\{ x:x$ is a student of class $\mathrm{XI}$ of your school $\} \ldots \{ x:x$ student of your school $\} $
Assume that $P(A)=P(B) .$ Show that $A=B$.
State whether each of the following set is finite or infinite :
The set of animals living on the earth
Which of the following are examples of the null set
$\{ y:y$ is a point common to any two parallellines $\} $