Answer:
<u>Instead of Helium and Hydrogen there are heavier elements in inner planets like Nitrogen and oxygen.</u>
Explanation:
- As the inner planets like Mercury, Venus and Mars and earth have a solid surface which is separated by the Sharpe atmosphere, and their gravity is too low to hold these light gases.
- Uranus is primarily composed of gases and ice of which 83% is hydrogen and 15% helium and rest are trace gases. As in the early composition of the atmosphere, the inner planets like the earth had a solid atmosphere composed of solid silicates elements like magnesium, iron, calcium, and potassium.
- As the earth has a highly unstable atmosphere only carbon, nitrogen and oxygen combined in lightning occur. And planet mercury has no atmosphere thus gravity is too low to hold any gas.
Layers of the soil are called horizons. Here are the horizons:
- Humus
- Topsoil
- Subsoil
- Fragmented rock
- Bedrock
Once a soil has developed, it forms layers called horizons. Beneath a surface layer of a plant remains, the topsoil is rich in decomposed plants and animal matter. The subsoil is mainly mineral particles, with much less organic material. The fragmented rock/bedrock is primarily small stones, and beneath it lies all bedrock.
Hope this answer helps you!
I believe that the answer to the first one is B, and the answer to the second question is C, i hope i helped!
Scientists can't be sure about the early atmosphere and can only draw evidence from other sources. For example, volcanoes release high quantities of carbon dioxide. Iron-based compounds are present in very old rocks that could only have formed if there was little or no oxygen at the time.
It depends on the species