Scientists<span> can tell by observing the seismic waves that are recorded all over the surface of the </span>earth<span> from distant earthquakes. The seismic waves are reflected (bounced off) </span>layers<span> of different density, and they are refracted (bent) when they enter </span>layers<span> of different density.</span>
Explanation:
hydrogen, oxygen and fluorine
The water cycle — technically known as the hydrological cycle — is the continuous circulation of water within the Earth's hydrosphere, and is driven by solar radiation. This includes the atmosphere, land, surface water and groundwater.
It was the planet Venus that made the spacecraft Magellan enable the scientists to make an extensive research. The spacecraft Magellan was a robotic space probe that was launched to observe the planet Venus and calculate the gravitational field of the planet.
Answer: The transfer of the minerals of the earth to living organisms and then back to the earth again is called a cycle
