Answer
$\frac{14}{3a}$
Work Step by Step
The quotient of two fractions is the first fraction multiplied by the reciprocal of the second fraction
If $\frac{a}{b}$ and $\frac{c}{d}$ are fractions and $\frac{c}{d}$ is not 0 then
$\frac{a}{b}\div \frac{c}{d}$ = $\frac{a}{b} * \frac{d}{c}$
So according to the above statement
$\frac{2}{3} \div \frac{a}{7}$ = $\frac{2}{3} * \frac{7}{a}$ = $\frac{2*7}{3*a}$ = $\frac{14}{3a}$