4 billion years ago the temperature was much higher due to repeated volcanoes and hot gases present in the atmosphere. There weren't any live forms on earth. ... The atmosphere had a different concentration of gases on the earth. There were no life sustaining gases.
Answer:
Fertilization occurs when the nucleus of both a sperm and an egg fuse to form a diploid cell,
Explanation:
Kepler-186f is an exoplanet that orbits around the red dwarf Kepler-186.
Explanation:
c. whale
are the viviparous as they bear live young .
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