Answer:
Photosynthetic organisms was the reason of these atmospheric changes.
Explanation:
The plant which is discovered by the scientists that is apparently devoid of life but has ice caps located at the poles which reveals that planet's atmospheric O₂ levels sharply increased about 1,000,000 years ago was due to evolution of photosynthetic organisms like cyanobacteria etc which went extinct and then O₂ levels dropped quickly 50,000 years ago. So photosynthetic organisms was the reason of these atmospheric changes.
Answer:
3x+y=45......equation 1
x-y=20......equation 2
Explanation:
There are now two equations, solve them using elimination or substitution method
I'm not 100% sure this is correct but this is the way I had learned.
The most practiced is Christianity
Because of gravity everything must come down
I believe that the answer is C)