Question 19-21 are based on the passage you have just heard.
A. Most of the early diamond miners became wealthy later.
B. Diamonds couldn't be formed without great heat and pressure of the volcano.
C. The earliest known diamonds were discovered in the River Amazon.
D. Explosions of the volcano can damage diamonds as well.
20
A. Under the river bed.
B. On the floor of the sea.
C. In the volcanoes.
D. At the foot of the mountains.
21
A. Diamond Hunting.
B. Diamond—A Precious Stone.
C. Diamond—Symbol of Fortune.
D. How Is Diamond Formed and Found?
Question 22-25 are based on the passage you have just heard.
A. The development of electronic musical instruments.
B. The relative costs of different types of musical instruments.
C. The performance of classical music on synthesizers.
D. The replacement of the harpsichord by the piano.
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