What has taken place in the Great Plains grasslands during the last century？
A. The average annual rainfall has risen and fallen several times
B. Large parts of the prairie have been converted to agricultural use
C. Melting glaciers have formed numerous depressions in the soil
D. Scientists have transformed the region into one large carbon sink
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According to the professor, what defines action art？ Click on 2 answer choices.
A. Control
B. Design
Coincidence
D. Imbalance
Why does the author use the term hard-wired in describing the sense of smell and the brain？
A. To describe the texture and feel of the olfactory nerve
B. To emphasize the close connection between smell and the brain
C. To compare the power of smell with that of other senses
D. To explain how the sense of smell evolved in early humans
The first colonists returned to England mainly because
A. they were attacked by the Indians.
B. they didn't have adequate supplies.
C. they had no passion for their new home at all.
D. they didn't receive enough financial aid.
The word which in paragraph 6 refers to
A. learning
B. study
C. list
D. smell
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