<u>Answer:
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The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
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- 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.
The first recorded use of the name Clydesdale in reference to the breed was in 1826 at the exhibition in Glasgow. Another theory of their origin, that of them descending from the Flemish horses brought to Scotland as early as the 15th century, was also promulgated in the late 18th century.
- You are welcome :) sorry i'm late
