Our galaxy is created by a huge explosion. Earth and the planets were created by the explosion of a huge acre of rock. The middle of the rock was very hot. So each planet was very hot at the time of creation. Then the earth gradually cools down and life begins to exist on earth. As far as I know, the first animal is the dinosaur. But I can't say if it's before. Anyway. Then the dinosaur began to become extinct after a huge rock fell on the earth.
And the reason for naming methane gas. About 80%. The material is methane. That is why it is called methane.
CO2 is produced by all aerobic organisms when they metabolize organic compounds to produce energy by respiration.[11] It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals, including humans. Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread, beer and wine making. It is produced by combustion of wood, peat and other organic materials and fossil fuels such as coal, petroleum and natural gas. It is an unwanted byproduct in many large scale oxidation processes, for example, in the production of acrylic acid
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