Which of the following are sets ? Justify your answer.
A collection of novels written by the writer Munshi Prem Chand.
Let $A=\{1,2,\{3,4\}, 5\} .$ Which of the following statements are incorrect and why ?
$\{ 3,4\} \in A$
Let $A=\{1,2,3,4,5,6\} .$ Insert the appropriate symbol $\in$ or $\notin$ in the blank spaces:
$ 8\, .......\, A $
Examine whether the following statements are true or false :
$\{ a,e\} \subset \{ x:x$ is a vowelin the English alphabet $\} $
Examine whether the following statements are true or false :
$\{a\} \subset\{a, b, c\}$