The problem: Answer a question about this article:
Cold or oxygen-rich atmospheres can sustain life at pressures much lower than atmospheric, as long as the density of oxygen is similar to that of standard sea-level atmosphere. The colder air temperatures found at altitudes of up to 3 km generally compensate for the lower pressures there. Above this altitude, oxygen enrichment is necessary to prevent altitude sickness in humans that did not undergo prior acclimatization, and spacesuits are necessary to prevent ebullism above 19 km. Most spacesuits use only 20 kPa (150 Torr) of pure oxygen. This pressure is high enough to prevent ebullism, but decompression sickness and gas embolisms can still occur if decompression rates are not managed.
density of oxygen like that of sea-level atmosphere is needed to do what?
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The answer: sustain life at pressures much lower than atmospheric,

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When power is lost in a traction elevator system, all elevators will initially come to a halt. One by one, each car in the group will return to the lobby floor, open its doors and shut down. People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will return to the lobby shortly. Once all cars have successfully returned, the system will then automatically select one or more cars to be used for normal operations and these cars will return to service. The car(s) selected to run under emergency power can be manually overridden by a key or strip switch in the lobby. In order to help prevent entrapment, when the system detects that it is running low on power, it will bring the running cars to the lobby or nearest floor, open the doors and shut down.
What do any passengers experience at this point?
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The answer: People in the remaining elevators may see an indicator light or hear a voice announcement informing them that the elevator will return to the lobby shortly

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Czech has one of the most phonemic orthographies of all European languages. Its thirty-one graphemes represent thirty sounds (in most dialects, i and y have the same sound), and it contains only one digraph: ch, which follows h in the alphabet. As a result, some of its characters have been used by phonologists to denote corresponding sounds in other languages. The characters q, w and x appear only in foreign words. The hacek () is used with certain letters to form new characters: s, z, and c, as well as n, e, r, t, and d (the latter five uncommon outside Czech). The last two letters are sometimes written with a comma above (', an abbreviated hacek) because of their height. The character o exists only in loanwords and onomatopoeia.
In Czech, what type of words do the characters "q", "w" and "x" exclusively appear in?
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The answer: foreign

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This view is supported by a study of the region where these notions originated. Buddhism arose in Greater Magadha, which stretched from Sravasti, the capital of Kosala in the north-west, to Rajagrha in the south east. This land, to the east of aryavarta, the land of the Aryas, was recognized as non-Vedic. Other Vedic texts reveal a dislike of the people of Magadha, in all probability because the Magadhas at this time were not Brahmanised.[page needed] It was not until the 2nd or 3rd centuries BCE that the eastward spread of Brahmanism into Greater Magadha became significant. Ideas that developed in Greater Magadha prior to this were not subject to Vedic influence. These include rebirth and karmic retribution that appear in a number of movements in Greater Magadha, including Buddhism. These movements inherited notions of rebirth and karmic retribution from an earlier culture[page needed]
Greater magadha stretched from Sravasti in the north-west to what area in the south-east?
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The answer:
Rajagrha