Question

question 5 of this exercise

Answer 1

this is answer hope it will help you thanks

Answer 2

 $7^{-1} = \frac{1}{7}$ & $3^{-1} = \frac{1}{3}$
which means the bracket's value would be:-
$\frac{1}{3}* \frac{1}{7}=\frac{1}{21}$
the $7^{-1}$ in the denominator moves to numerator becoming $7^{1}$
thus the simplified equation would be:-
$\frac{7}{21}$ = $\frac{1}{3}$

hope this helps!