The lower oxygen pressure found in an aircraft cabin is equivalent to that at 6,000-8,000 feet of altitude.

机舱里的氧分压会更低，其数值跟6000到8000英尺高空的氧分压值一样。

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As well as the bitter cold, they will have to cope with life on the Antarctic Plateau, with the reduced levels of oxygen that comes from being located at 3, 800 meters (12, 470 feet) equivalent altitude.

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That wind was traveling at 120 miles an hour, so we ended up with Felix in the capsule under this 30-million-cubic-foot balloon flying at 125 miles an hour to the east, which is amazing to think about, because at that altitude, it's the equivalent of about a 50-story building.

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