Problem: Sahara:

By 3400 BCE, the Sahara was as dry as it is today, due to reduced precipitation and higher temperatures resulting from a shift in the Earth's orbit. As a result of this aridification, it became a largely impenetrable barrier to humans, with the remaining settlements mainly being concentrated around the numerous oases that dot the landscape. Little trade or commerce is known to have passed through the interior in subsequent periods, the only major exception being the Nile Valley. The Nile, however, was impassable at several cataracts, making trade and contact by boat difficult.

What caused the shift in the earth's orbit?
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A: unanswerable


Problem: Hunting:

Varmint hunting is an American phrase for the selective killing of non-game animals seen as pests. While not always an efficient form of pest control, varmint hunting achieves selective control of pests while providing recreation and is much less regulated. Varmint species are often responsible for detrimental effects on crops, livestock, landscaping, infrastructure, and pets. Some animals, such as wild rabbits or squirrels, may be utilised for fur or meat, but often no use is made of the carcass. Which species are varmints depends on the circumstance and area. Common varmints may include various rodents, coyotes, crows, foxes, feral cats, and feral hogs. Some animals once considered varmints are now protected, such as wolves. In the US state of Louisiana, a non-native rodent known as a nutria has become so destructive to the local ecosystem that the state has initiated a bounty program to help control the population.

What are nutria often used for when hunted?
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A: unanswerable


Problem: Phonology:

Part of the phonological study of a language therefore involves looking at data (phonetic transcriptions of the speech of native speakers) and trying to deduce what the underlying phonemes are and what the sound inventory of the language is. The presence or absence of minimal pairs, as mentioned above, is a frequently used criterion for deciding whether two sounds should be assigned to the same phoneme. However, other considerations often need to be taken into account as well.

What type of language study involves trying to deduce underlying phonomes?
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A: phonological


Problem: Czech language:

One study showed that Czech and Slovak lexicons differed by 80 percent, but this high percentage was found to stem primarily from differing orthographies and slight inconsistencies in morphological formation; Slovak morphology is more regular (when changing from the nominative to the locative case, Praha becomes Praze in Czech and Prahe in Slovak). The two lexicons are generally considered similar, with most differences in colloquial vocabulary and some scientific terminology. Slovak has slightly more borrowed words than Czech.

When is Praha morphology more regular than scientific terminology?
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A:
unanswerable