Find the pairs of equal sets, if any, give reasons:

$A = \{ 0\} ,$

$B = \{ x:x\, > \,15$ and $x\, < \,5\} $

$C = \{ x:x – 5 = 0\} ,$

$D = \left\{ {x:{x^2} = 25} \right\}$

$E = \{ \,x:x$ is an integral positive root of the equation ${x^2} – 2x – 15 = 0\,\} $

Write the following intervals in set-builder form :

$\left( {6,12} \right]$

The number of elements in the set $\{x \in R :(|x|-3)|x+4|=6\}$ is equal to

Given the sets $A=\{1,3,5\}, B=\{2,4,6\}$ and $C=\{0,2,4,6,8\},$ which of the following may be considered as universal set $(s)$ for all the three sets $A$, $B$ and $C$

$\varnothing$

State which of the following sets are finite or infinite :

$\{ x:x \in N$ and $x$ is prime $\} $