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

$ 2 \, ....... \, A $

Which of the following are sets ? Justify your answer.

The collection of all even integers.

What universal set $(s)$ would you propose for each of the following :

The set of right triangles

From the sets given below, select equal sets:

$A=\{2,4,8,12\}, B=\{1,2,3,4\}, C=\{4,8,12,14\}, D=\{3,1,4,2\}$

$E=\{-1,1\}, F=\{0, a\}, G=\{1,-1\}, H=\{0,1\}$

Which of the following is a true statement

Which set is the subset of all given sets