Trace the major processes in the evolution of the earth's atmosphere from its beginning to the present
What will be an ideal response?
Answer: The atmosphere has been greatly transformed since its early days rich in water vapor and carbon dioxide. The removal of the water vapor is easily explained: Upon cooling in the prehistoric atmosphere, it readily condensed and precipitated to the surface to form the oceans. Precipitation also contributed to the removal of carbon dioxide from the atmosphere. As raindrops fell through the CO2-rich atmosphere, some CO2 was dissolved in every drop. The transformation to an atmosphere high in oxygen depended on the advent of primitive, anaerobic bacteria (those that survive in the absence of oxygen) about 3.5 billion years ago. These primitive life-forms were the first in a long line of organisms that removed carbon dioxide from the air and replaced it with oxygen (these gases are exchanged freely between the oceans and the atmosphere). All of these processes gradually led to an increase in atmospheric oxygen at the expense of carbon dioxide. Although it constitutes a small portion of the material released by outgassing, nitrogen is removed from the atmosphere very slowly. As a result, its concentration has gradually increased to the point that it is now the main constituent of the atmosphere. Finally, argon, the third most abundant gas, is explained by slow seepage from the solid Earth of argon-40 with its 18 protons and 22 neutrons.
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Which of the following would be an example of qualitative data?
A) A physical geographer measuring the time required for a plume of air pollution to reach a town B) A physical geographer taking a census of the number of pine trees infested with a certain disease C) A physical geographer monitoring the water temperature in a stream D) A physical geographer noting the color of a soil
What is the gradient of a stream? What will be an ideal response?
The philosophy of classical economics developed by Adam Smith ________
A) assures equality between rich and poor B) advocates free-market policies that many credit for the tremendous gains in material prosperity of industrial nations C) proposes maintenance of economies through government restraint and regulation D) was adopted by the Aborigines in the Kakadu region of Australia E) argues that individuals acting in their own self-interest harm society
Which of the following slope failures is most likely to cause large numbers of casualties?
A. creep B. rotational slide C. debris slide D. rock avalanche E. earth flow