<u>Answer:
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The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
</u>
- The ozone layer is a part of the stratosphere which is located right after the troposphere in the atmosphere of the Earth.
- The ozone gas is made up of the abundance of three oxygen molecules combining with the ultraviolet radiation emitted by the Sun.
- The development of the ozone layer happened around two billion years ago when the oxygen concentration levels on the planet began to rise slowly and gradually.
Outwash plain is a landscape feature created by glacial deposits.
The answer is; C
The study of plant and animal life in an environment is known as ecology. Anthropology is mainly defined as the study of humans, their behaviors and societal norms and values (such as politics, culture, religion, and language), in the past and present.
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.