Why are ores so valuable?
A. They are sources of naturally occurring gold.
B. They hold many clues to Earth's natural history.
C. Metals can be efficiently extracted from them.
D. They tend to occur in scenic mountainous regions.
Answer: C
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Waves
A) are usually formed by the effect of tides. B) travel with equal energy in all directions from the point of origin. C) have speeds that are proportional to wavelength. D) change more in deep water than in shallow water.
What is the driving mechanism for plate tectonics?
A)heat deep within Earth B)tidal forces caused by the moon C)volcanoes and earthquakes at plate boundaries D)gravity and magnetism acting on continents E)strong ocean currents and global winds
Which of the following is involved in the synthesis of bile salts?
A) hydrolysis B) oxidation C) reduction D) all of these
____ exist where continental glaciers meet the ocean
a. Outlet glaciers b. Icebergs c. Erratics d. Outwash plains