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.
The journals were based upon the field diaries that explorers were required to keep by the Colonial Office. The explorers' field diaries and journals were also of vital importance for the information they contained about possible economic benefits that could be derived from the land.
Answer:
It is C
Explanation:
Adversity prompted the Somalis to test new ways of making money and former fishermen joined hands with the militia and unemployed youth to hijack vessels and demand ransom. This was the start of piracy in Somalia.
Answer:
The Great Lakes and Corn Belt occupies a significant portion of this subregion located between the Appalachian Mountains to the east and the Rocky Mountains to the west named A. America’ s central lowlands.