The correct answer is - cyanobacteria.
The atmospheric oxygen came from the cyanobacteria. These were one of the earliest living organisms on Earth. The cyanobacteria was using photosynthesis in order to create its own food. The photosynthesis process requires sunlight, carbon dioxide, water, and oxygen. The oxygen is mostly released as a waste product from the process of photosynthesis, thus the cyanobacteria were literally releasing oxygen that was ending up into the atmosphere. As more and more cyanobacteria there were across the planet, more and more oxygen they were releasing into the atmosphere, slowly changing the composition of the atmosphere, and setting the basis of it as we know it now.
Salutations!
<span>What type of boundary occurs along the Aleutian islands in the north pacific?
Convergent boundaries occur along the Aleutian islands in the north pacific.
Hope I helped!
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The correct answer is:
C) NAFTA encourages trade between Mexico, U.S. and Canada.
Explanation:
The North American Free Trade Agreement or NAFTA was an agreement signed between Canada, the USA and Mexico on January 1, 1994 establishing a trade bloc between the three.
