State whether each of the following set is finite or infinite :

The set of numbers which are multiple of $5$

State whether each of the following set is finite or infinite :

The set of animals living on the earth

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

$\{\varnothing\} \subset A$

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

$ 5\, .......\, A$

Write the following as intervals :

$\{ x:x \in R, - 12\, < \,x\, < \, - 10\} $

Write the following sets in roster form :

$D = \{ x:x$ is a prime number which is divisor of $60\} $