Please help me on questions 3 and 6, thank you! :D I'll give brainliest!

3. if you increase your mass you also increase the gravitational pull

6. Radiant energy doesn't depend on a medium and sound energy is dependent on a medium.

Explanation:

i hope this helps-

3. To increase gravitational pull to the earth, the more mass an object has, the stronger the gravitational pull, so increase mass.

6. While sound energy depends on a medium, radiant energy uses it's own sources to stay independent from other mediums.

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.