If $\mu_0$ is permeability of free space and ε0 is permittivity of free space, the speed of light in vacuum is given by

$\sqrt{\mu_0ε_0}$ $\sqrt{\frac{\mu_0}{ε_0}}$ $\sqrt{\frac{1}{\mu_0ε_0}}$ $\sqrt{\frac{ε_0}{\mu_0}}$

$\sqrt{\frac{1}{\mu_0ε_0}}$

The speed of light in vacuum is given by $\sqrt{\frac{1}{\mu_0ε_0}}$, where $\mu_0$ is permeability and ε0 is permittivity of free space.