Why is grain production in the Great Plains considered largely unsustainable?
A) Competition with cattle ranching is resulting in a decline in crop production.
B) More and more people are becoming gluten intolerant, so there will be less and less demand for wheat, barley, and rye.
C) The Ogallala aquifer is being depleted for irrigation water.
D) The energetics of crop production in the Great Plains are such that more energy is needed to grow the crops than can be gotten from the crops.
E) So many pesticides are needed for grain production that streams in the Great Plains are becoming dead zones.
Answer: C
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San Francisco, CA and Wichita, KS are located at approximately the same latitude. Which of the following is TRUE?
A) On average, December temperatures in San Francisco tend to be lower than those in Wichita. B) Summer temperatures in San Francisco far exceed those of Wichita. C) Annual temperature ranges in Wichita are greater than those in San Francisco. D) San Francisco experiences several months with average temperatures below the freezing point. E) Minimum average temperatures in Wichita are consistently lowers than those in San Francisco.
What energy source causes the most air pollution per unit of energy produced?
A. coal B. natural gas C. uranium D. gasoline
Name two features defined by the principle of cross-cutting relationships
A) convergent tectonic plates and faults B) faults and dikes C) dikes and sills D) convergent tectonic plates and sills
Which of the following human activities can contribute to mass movement?
A) A roadcut B) Residential and commercial development C) Surface mining D) Any human disturbance of a slope, including road cuts, surface mining, and residential and commercial development.