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 negative impacts of radiation on a country's economy may include :
- Increased rate of mortality
- Destruction of food crops and cattles
- Environmental contamination
- Long term health complications
Radiation has proven to be very useful in medicine, power, defense and other sectors if adequately deployed. However, it's negative impact can also be overwhelming.
Some of the negative impacts of radiation include :
- Radiation could cause death thousand to millions of people within minutes. Such could result from bomb attacks or release of toxic nuclear substances into the environment.
- The effect of radiation does not only pose risk to life, it could also lead to destruction of crops and cattles. Causing famine and unquantifiable losses.
- Nuclear radiation may be so deadly that it renders several Radius or perimeter of an environment inhabitable. Such is the situation of Hiroshima and Nagasaki.
- Nuclear radiation often poses the risk of terminal diseases such as cancer upon exposure .
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Answer:
I am not entirely sure about this one. But I believe that the "Emancipation Manifesto" signed by Czar Alexander II gave serfs land, or at least gave them the freedom to do what they wanted, like buying that said land.
No freedom of religion, or elections was yet to be had in Russia.
Explanation:
The climate of the costal plain is mild. It has hot summers and cool winters and few hard freezes.
Answer:
planetesimal assembly
Explanation:
The accretion model, also known as planetesimal assembly, is what gives us the perspective for the formation of the astronomical objects via the process of accretion. Some of the astronomical objects that are formed by this process are the galaxies, stars, planets,and moons. The process of accretion represents the accumulation of particles into an object by gravitationally attracting more and more matter, mostly gaseous matter, forming an accretion disk.