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.
Answer:
Cyclones and ocean currents transport heat towards the poles
Explanation:
The reason why the tropics is not getting hotter and the poles not getting colder is due to the activities of cyclones and ocean currents which transport heats towards the poles thus enabling the temperatures at the tropics and the poles to remain fairly constant.
An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences.
The city of Los Angeles released 96 million "shade balls" into the Los Angeles Reservoir. These will serve to shield the water from the sun's heat in order to reduce evaporation and prevent algal and bacterial growth so no toxic substances are produced in the water. The balls reduce evaporation by 85%-90% so will save a lot of water yearly.
