Questions 57-62 are based on the following passage.
Since life began eons ago, thousands of creatures have come and gone. Some, such as the dinosaurs, became extinct due to naturally changing ecologic conditions. More recent threats to life forms are humans and their activities. Man has drained marshes, burned prairies, dammed and diverted rivers. Some of the more recent casualties of man's expansion have been the dodo, great auk, passenger pigeon, Irish elk, and Steller's sea cow. Sadly, we can no longer attribute the increasing decline in our wild animals and plant species to "natural" processes. Many species are dying out because of exploitation, habitat alteration or destruction, pollution, or the introduction of new species of plants and animals to an area. As mandated by Congress, protecting endangered species, and restoring them to the point where their existence is no longer jeopardized, is the primary objective of the U.S. Fish and Wildlife Service's Endangered Species Program.
57. Which of the following is a form of man's habitat alteration?
A. Glacial encroachment
B. Hurricanes
C. Dammed rivers
D. Snowstorms
58. Which of the following has become extinct due to man's destruction?
A. African elephant
B. Irish elk
C. Giant panda
D. White Bengal
Questions 63-68 are based on the following passage.
The "Karat" marking on jewelry tells you what proportion of gold is mixed with other metals. If 14 parts of gold are mixed with 10 parts of base metal, the combination is called 14-Karat (14K) gold. The higher the Karat rating, the higher the proportion of gold in the object. The lowest Karat gold that can be marketed in the United States is 10-Karat gold. Jewelry does not have to be marked with its Karat quality, but most of it is. If there is a Karat quality mark, next to it must be the U.S. registered trademark of the person or company that will stand behind the mark, as required by the National Gold and Silver Stamping Act.
63. If a ring is stamped 24K, it has
A. 204 parts of gold.
B. 24 parts of gold.
C. two and four-tenths parts of gold.
D. 10 parts of gold.
64. Gold which is 10 Karats in proportion
A. represents the highest grade of gold in the U.S.
B. cannot be sold in the U.S.
C. never carries a Karat quality mark.
D. represents the lowest-grade gold marketable in the U.S.
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