Question

The speed of electromagnetic wave in a medium
(whose dielectric constant is 2.25 and relative
permeability is 4) is equal to
(1) 0.5 * 10^8 m/s
(2) 0.25 * 10^8 m/s
(3) 0.75 * 10^8 m/s
(4) 1 * 10^8 m/s
​

Answer 1

Answer is
no.4
$\frac{?}{?} \times \frac{?}{?}$