How long could divers stay underwater in Halley's bell?
C
Những thợ lặn có thể ở dưới nước bao lâu trong cái chuông của Halley?
A. một vài giây
B. một vài phút
C. khoảng vài giờ một lần
D. khoảng vài ngày
Dẫn chứng: Halley's bell was an improvement in that its design allowed for an additional supply of fresh air that enabled a crew of divers to remain underwater for several hours.
=>Chọn C
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According to the passage, what special honor did Eagan receive in 1983?
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