If we will base our answer on Hertzsprung diagram, we
will see that mass and luminosity are directly related, which means, long lived
stars begin their lives with more mass and a larger amount of hydrogen fuel,
hence hydrogen is abundant before than now. They are more luminous during their
main sequence lives. Giant stars and supergiant
stars have great masses, so, they have greater luminosities.
<span> </span>
Between 1931 and 1940 a ton of soil blew out of the central and southern great. It was a period of severe dust storms that greatly damaged the ecology and agriculture during the 1930s.
Because Cyanobacteria appeared
Cyanobacteria's excrement formed a lot of oxygen in the atmosphere which make the earth temperature cold
This allow a liquid water to formed on the surface ( because if the temperature is too high, the water will evaporate) and eventually formed oceans
Answer:
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