A state is in a country, a country is in a continent. The main difference is size. a state can be really populated, but a country is more populated. a continent is even more populated then that. Hope this helps
Earth was able to retain an atmosphere because of its gravity. It is <span>the same force that keeps us anchored to Earth. Molecules in our atmosphere are constantly moving, spurred on by energizing sunlight. If Earth were much less massive, gravity's grip would be weaker.</span>
Answer:
The correct answer is D
Explanation:
During the 20th century, there was an increasing interest in the environment. The impact of human activity on the environment has been observed locally since centuries. Pollution of canals and chimneys in crowded urban areas etc were all causes of concern.
However, with a better understanding of our earth and increase in Medical knowledge of the 20th century, we could observe how our activities were having a global impact on the ozone layer and the melting ice caps.
Evidence was also provided on how human health was affected by this. The use of fossil fuels was not only directly damaging to the atmosphere, it was also dangerous for humans e.g. carbon monoxide produced by car emissions.
