Simplify (4x^0)/(y^-3)

$\frac{4 x^{0}}{y^{- 3}}$

Move $y^{- 3}$ to the numerator using the negative exponent rule $\frac{1}{b^{- n}} = b^{n}$ .

$4 x^{0} y^{3}$

Anything raised to $0$ is $1$ .

$4 \cdot 1 y^{3}$

Multiply $4$ by $1$ .

$4 y^{3}$