1. The correct answer is I and II only. The increase in population leads to a bigger pollution in water due to the cycle it follows (being used by humans to their living processes, excrements, etc), the air gets more polluted due to the respiratory chain (more production of Carbon dioxide) and by transportation which use fossil fuels and produce harmful gases and also the noise increases because of the industries, cars and even conversation comes to a higher level in quantity and volume.
2. An effective component to create a more sustainable environment would be the reduction of fossil fuels usage, because they produce carbon dioxide and other toxic gases. Pollution regulations should be kept or strenghthened, birth rates should be kept to a balanced rate, plastic bags shall be reduced to a minimum because the time demanded to be decomposed is longer than paper ones and importing food staples from other countries does not make a sustainable environment.
3. An indirect source of pollution is placing an online order for a CD to be shipped from another state. That is so because the ship will produce pollution to commute from one place to the other as it depends on fuel to work.
4. A good policy to make a relatively poor nation more sustainable would be the offer of financial incentives for limiting family size. That is so because birth rates are usually very high in poor nations. As known, the bigger the number of citizens, the lower the conditions for well being and health we may have. By limiting the birth rate, the government would have to invest less in social policies (health insurance, security and education) which cost the most.
5. The answer is D. That is so because the industrial revolution made people migrate to the cities to get work, which made the number of population rise. After that period the number fell because of diseases, high birth growth and people who died or returned to their origin places.
6. The type of society that has the greatest overall impact is the industrial one, because it involves more pollution sources of air, water and noise; more littering and consumerism of the sources available in the area.
7. The aspect of society that more contributed to the plague was the high population density. Once one person was sick and there were no appropriate conditions for living, such as potable water, hygiene and healthy food, as well as the lack of space to segregate sick ones, the plague quickly spread all over, contaminated and killed many.
8. The answer is letter E. As a consequence of the bad results of industries, the population learns how to deal with challenges related to pollution and migration increases. As a consequence of this increase, families grow, as birth rates raise and there´s a big boom of new-borns.
9. A water system is more likely to be contaminated by point source pollution when farmers spray their fields with chemical pesticides, which seep through the soil and into the groundwater supply. That is so because these chemicals demand long time to be biodegradated and also because the contamination of freatic/ water streams is so serious cause the chemicals get spread from underground and spred very fast.
10. The best sentence to describe the "Tragedy of the commons" is that faced with threats to the environment, some people willingly sacrifice individual rights for the benefit of society. Once the community needs to be preserved it´s mandatory that the group´s interests come above all the individuals rights.
