How do geologists know that the magnetic field of Earth has changed constantly over time?
A) by the direction of historical lava flows, which they have been able to date with radioactive dating methods
B) by crystals that have formed in metamorphic rocks
C) by records kept in magnetic rock-forming minerals
D) by analyzing and extrapolating records kept by scientists since the 1600s
Answer: C
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Dealing with conflicts between scientific solutions and political solutions usually involves making ____________________.
Fill in the blank(s) with the appropriate word(s).
Which of the following temperature changes will most likely coincide with an increase in atmospheric CO2 concentrations?
A. warming in the troposphere and warming in the upper atmosphere B. warming in the troposphere and cooling in the upper atmosphere C. cooling in the troposphere and cooling in the upper atmosphere D. cooling in the troposphere and warming in the upper atmosphere
What European mountain range forms the political border between Spain and France?
A) Pyrenees B) Alps C) Carpathians D) Dinaric Alps E) Apennines
Taken as a whole, the large scale or general circulation patterns of the atmosphere exist:
A) because of the earth's rotation. B) as a result of the different landforms on Earth's surface. C) as nature's method of balancing heat energy differences. D) as a cause of temperature contrasts. E) as a result of Earth's motion through space.