Write the following sets in roster form :

$\mathrm{F} =$ The set of all letters in the word $\mathrm{BETTER}$

Write the set $\left\{\frac{1}{2}, \frac{2}{3}, \frac{3}{4}, \frac{4}{5}, \frac{5}{6}, \frac{6}{7}\right\}$ in the set-builder form.

Assume that $P(A)=P(B) .$ Show that $A=B$.

Which of the following are sets ? Justify your answer.

The collection of ten most talented writers of India.

From the sets given below, select equal sets:

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

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