Passage Three Questions 23 to 25 are based on the passage you have just heard.
A. To keep the heat inside.
B. To prevent insects from escaping.
C. To reduce the risk of fire.
D. To keep the wood dry.
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Passage Two Questions 19 to 22 are based on the passage you have just heard.
A. They become less fuel-efficient.
B. They have trouble staying on the tracks.
C. They produce too much noise.
D. They are subject to fires.
Passage Three Questions 23 to 25 are based on the passage you have just heard.
A. To show one of the dangers of the old method.
B. To explain one step in the new technique.
C. To show that there is no danger from the treatment.
D. To explain a compromise between old and new systems.
Passage Two Questions 19 to 22 are based on the passage you have just heard.
A. It carries more passengers than a conventional train.
B. It doesn’t remain in any station very long.
C. It doesn’t require very much track maintenance.
D. It is more comfortable than a conventional train.
Passage Three Questions 23 to 25 are based on the passage you have just heard.
A. The new system is cheaper.
B. The new system is quicker.
C. The new system is safer.
D. The new system is available anywhere.
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