How have scientists been able to determine the composition of earth’s layers?

I believe scientists have been able to determine the composition of the Earth's layers through seismic waves.  Hope this helped!

-TTL

The correct answer is with the help of seismic waves.

Explanation:

The majority of what we know about the interior of the Earth is mainly because of the seismic waves. These are the waves of energy, which can be a result of earthquakes. The two prime kinds of seismic waves are the surface waves and the body waves.  

The surface waves move only along the Earth's surface, while the body waves move through the interior of the Earth in all the directions. It is the body waves behavior, which has provided the clues to the scientists regarding the composition of the Earth's layers. There are two kinds of body waves, these are the primary and the secondary waves.  

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.