Answer
$\dfrac{a^{-4}b^7}{c^{-3}} =\dfrac{b^7c^3}{a^4}$
Work Step by Step
RECALL:
The negative-exponent rule of exponents states that:
$a^{-m} =\dfrac{1}{a^m}$ and $\dfrac{1}{a^{-m}} = a^m$, where $a \ne 0$.
Use the negative-exponent rule to find:
$\dfrac{a^{-4}b^7}{c^{-3}} =\dfrac{\frac{b^7}{a^4}}{\frac{1}{c^3}}=\dfrac{b^7}{a^4} \cdot \dfrac{c^3}{1}=\dfrac{b^7c^3}{a^4}$