Check that associative property holds for division of given rational numbers: $15$ and $3$

Verify the statement and name the property of multiplication illustrate by these statements:

$\left(\frac{3}{4}\times \frac{1}{2}\right) \times \frac{5}{7}=\frac{3}{4}\times \left(\frac{1}{2}\times \frac{5}{7}\right)$

Find the multiplicative inverse i.e. the reciprocal

$\frac{4}{5}\times \frac{15}{8}$

Find the multiplicative inverse i.e. the reciprocal of

$0\times \frac{2}{9}$

Find the multiplicative inverse i.e. the reciprocal of

$\frac{-19}{16}$

Write the reciprocal of the following with a positive exponent.