Which is the correct expression of velocity of light?

$\frac{1}{\sqrt{\varepsilon_0 \mu_0}}$ $\frac{E_0}{B_0}$ $\frac{c}{\mu}$ All of these

All of these

The velocity of electromagnetic waves in free space is given by $c=\frac{1}{\sqrt{\mu_0 \varepsilon_0}}=\frac{E_0}{B_0}=3 \times 10^8 ms^{-1}$ Moreover, velocity of light in a medium with refractive index µ is, v = $\frac{c}{µ}$