Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O
2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".
Answer:
the answer is C
Animals get the nitrogen they need by eating plants or other animals that contain nitrogen. When organisms die, their bodies decompose bringing the nitrogen into soil on land or into ocean water. Bacteria alter the nitrogen into a form that plants are able to use
<span>Scientists believe that tectonic activity is not occurring on the moon. This is <span>because the moon lacks radioactive decay. The moon is not constantly supplied heat and energy from decaying unstable isotopes like Earth. Also, Earth is heated by the original heat during its formation. Since the moon was most likely broken off from earth, it lacks this central heat. @Kb0812 Hope this helps and if your feeling generous feel free to leave a rate, thanks and brainliest because it would really help me reach expert and I would appreciate it ;)</span></span>
A nucleotide is an organic molecule that is the building block of DNA and RNA. ... A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base. The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine. RNA contains uracil, instead of thymine.
Hopefully this helped! :D
-LavenderVye
Human error
We can most probably assume that there was the presence of
error. Error comes in two types with regards to measurement. The systematic
errors and random errors. However, this is either caused by human errors. Human
errors are a natural phenomenon that occurs either because of inexperience in
using a measuring device or the unconscious behaviors and modifications done.
In this case, we can assume Dawn was hypothetically inept and wasn’t properly
oriented to use the measuring device.
