Answer:
It's the 4th, as third is modified by the man.
Explanation:
- The Third atmosphere was a rearrangement of the plate tectonics and the evolution of atmosphere by the transferring of it to the oceanic basins. As the amount of oxygen in the atmosphere used to be more than 30% around 280 million years ago than the present.
- Rapid development of land plants and animals was caused due to this atmosphere and hence this atmosphere is now less than 21% and due to his influence or modification of man with his technological tools and techniques.
- The atmosphere is rapidly shrinking due to the greenhouse effect and global warming that is leading to the fifth atmosphere that may be like that of mars as devoid of gases and barren and dry with oceans running under the crust.
Answer:
Explanation: Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of chemical substances or energy, such as noise, heat, or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.
Answer:
Which of the following countries has the lowest arithmetic density?
Canada.
<em>Arithmetic density means the number of inhabitants per unit of measurement. </em>
The lowest arithmetic density is in Canada because:
- <em>it has large areas of boreal forest (conifers).
</em>
- <em>there are very low temperatures and an unfavorable climate is present (especially in the northern part of Canada).</em>
