The chief ingredient of most solar cells is ____.
A. silicon
B. sodium
C. chromium
D. arsenic
E. calcium
Answer: A
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Beneficial insects are used in agriculture to do all of the following EXCEPT
A. produce beneficial bacteria. B. pollinate flowers. C. eat pest weeds. D. prey on pest insects.
Citizen science and citizen involvement in policy formulation
A) make it even more difficult to enact international environmental policy. B) can help move policymaking out of the hands of special interest groups into law. C) have generally hampered local policies to fix environmental problems. D) are a continuing source of junk science and misinformed opinion.
The removal of existing dams is motivated by
A) the need for more urban drinking water. B) the need for more irrigation water. C) restoration of scenic beauty of rivers and fisheries. D) the need for more hydroelectric power stations.
When magma forms, it rises up through the crust. Why does magma rise?
A) It is forced upward by pressure from the Earth's interior. B) It is less dense. C) It is uplifted by tectonism. D) It is forced out by volcanism.