Problem: Indigenous peoples of the Americas:

Various theories for the decline of the Native American populations emphasize epidemic diseases, conflicts with Europeans, and conflicts among warring tribes. Scholars now believe that, among the various contributing factors, epidemic disease was the overwhelming cause of the population decline of the American natives. Some believe that after first contacts with Europeans and Africans, Old World diseases caused the death of 90 to 95% of the native population of the New World in the following 150 years. Smallpox killed up to one third of the native population of Hispaniola in 1518. By killing the Incan ruler Huayna Capac, smallpox caused the Inca Civil War. Smallpox was only the first epidemic. Typhus (probably) in 1546, influenza and smallpox together in 1558, smallpox again in 1589, diphtheria in 1614, measles in 1618all ravaged the remains of Inca culture.

How did smallpox cause the Inca Civil War?
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A: By killing the Incan ruler Huayna Capac

Problem: Separation of church and state in the United States:

Many early immigrant groups traveled to America to worship freely, particularly after the English Civil War and religious conflict in France and Germany. They included nonconformists like the Puritans, who were Protestant Christians fleeing religious persecution from the Anglican King of England. Despite a common background, the groups' views on religious toleration were mixed. While some such as Roger Williams of Rhode Island and William Penn of Pennsylvania ensured the protection of religious minorities within their colonies, others like the Plymouth Colony and Massachusetts Bay Colony had established churches. The Dutch colony of New Netherland established the Dutch Reformed Church and outlawed all other worship, though enforcement was sparse. Religious conformity was desired partly for financial reasons: the established Church was responsible for poverty relief, putting dissenting churches at a significant disadvantage.

Who was persecuting the Puritans?
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A: King of England

Problem: Carnival:

Carnival celebrations, usually referred to as Mardi Gras (Fat Tuesday in French), were first celebrated in the Gulf Coast area, but now occur in many states. Customs originated in the onetime French colonial capitals of Mobile (now in Alabama), New Orleans (Louisiana) and Biloxi (Mississippi), all of which have celebrated for many years with street parades and masked balls. Other major American cities with celebrations include Washington, DC; St. Louis, Missouri; San Francisco; San Diego; Galveston, Texas; and Miami, Pensacola, Tampa, and Orlando in Florida.

What has been part of the celebrations for many years?
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A: street parades and masked balls

Problem: Catalan language:

With the union of the crowns of Castille and Aragon (1479), the use of Spanish gradually became more prestigious. Starting in the 16th century, Catalan literature experienced a decline, the language came under the influence of Spanish, and the urban and literary classes became bilingual.

When did Catalan literature begin a downward trend?
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A:
16th century