If you wanted to soundproof a room what insulator would you use

foam but thats what i heard from other people

Explanation:

If you want to make your insulation even more effective at blocking and absorbing noise that passes through walls or ceilings, you can add a few finishing touches before replacing the drywall. As I’ve explained in my article on the best wall soundproofing, you can add a layer of MLV over the insulation .

Explanation:

electromagnetic waves travel through space with vacuums. give me brainliest if right.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.