Ozone layer depletion was not noticed until 1979, while CFC’s have been around since 1920s because CFCs take time to enter the stratosphere and remain there for at least 60 years after their initial release.
Option: A
Explanation:
Ozone layer is found in stratosphere. Ozone plays a dual role in the environment. When it is in the ground surface zone it is a harmful gas but when its in the atmosphere it is a life saving layer which absorbs UV rays and protect human beings and animals from the harmful affect of poisonous gases.
Though ozone layer started depleting from 1920. But it came into notice from 1979 as CFCs take time to enter the stratosphere and remain there for at least 60 years after their initial release.
Kievan Rus was a loose federation of East Slavic and Finnic peoples in Europe from the late ... He extended his control from Novgorod south along the Dnieper river valley to protect trade from Khazar incursions ... In the south, in the area around Kiev, were the Poliane, a group of Slavicized tribes with Iranian origins
Answer: is south of north america
Explanation:
Photovolatics utilize "Solar" energy to produce electricity.
