Briefly explain how geologists can formulate theories about events that occurred on Earth before
humans were here to make observations. What will be an ideal response?
Geologists base their theories on two assumptions. First, that rocks record the processes that were
involved in formation of those rocks. Second, that uniformitarianism is true, and the present is the key
to the past. This means that basic physical, chemical, and biological processes have not changed, and
that if we study and understand them today, we can apply what we learn to conditions in the past.
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China, South Korea, the United Arab Emirates and Saudi Arabia are each buying and leasing millions of hectares of land around the world
A) on which to grow food for their own populations. B) to explore for minerals and energy resources. C) as real estate investments for their surplus money. D) to develop colonies for their expanding populations.
Which of the following islands is part of the Lesser Antilles?
A) Cuba
B) Hispaniola
C) Puerto Rico
D) Jamaica
E) St. Lucia
Which of the following describes how the atmospheric greenhouse effect is mainly produced?
A. Gases in the atmosphere absorb and re-emit ultraviolet radiation. B. Clouds absorb and re-emit visible light. C. Gases in the atmosphere absorb and re-emit infrared radiation. D. Gases in the atmosphere absorb and re-emit visible light.
What fraction of North America was covered by ice at the peak of the last ice age?
A) 1/4 B) 1/3 C) 2/3 D) 5/6