Problem: Umayyad Caliphate:

Ali was assassinated in 661 by a Kharijite partisan. Six months later in the same year, in the interest of peace, Hasan ibn Ali, highly regarded for his wisdom and as a peacemaker, and the Second Imam for the Shias, and the grandson of Muhammad, made a peace treaty with Muawiyah I. In the Hasan-Muawiya treaty, Hasan ibn Ali handed over power to Muawiya on the condition that he be just to the people and keep them safe and secure, and after his death he not establish a dynasty. This brought to an end the era of the Rightly Guided Caliphs for the Sunnis, and Hasan ibn Ali was also the last Imam for the Shias to be a Caliph. Following this, Mu'awiyah broke the conditions of the agreement and began the Umayyad dynasty, with its capital in Damascus.

When was a Kharijite partisan killed?
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A: unanswerable

Problem: Frederic Chopin:

Chopin's disease and the cause of his death have since been a matter of discussion. His death certificate gave the cause as tuberculosis, and his physician, Jean Cruveilhier, was then the leading French authority on this disease. Other possibilities have been advanced including cystic fibrosis, cirrhosis and alpha 1-antitrypsin deficiency. However, the attribution of tuberculosis as principal cause of death has not been disproved. Permission for DNA testing, which could put the matter to rest, has been denied by the Polish government.

What has the Polish government not allowed to find true cause of death?
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A: DNA testing

Problem: Imamah (Shia doctrine):

Although all these different Shia tariqahs belong to the Shia group (as opposed to the Sunni group) in Islam, there are major doctrinal differences between the main Shia tariqahs. After that there is the complete doctrinal break between all the different Shia tariqahs whose last Imams have gone into Occultation and the Shia Nizari Ismailis who deny the very concept of Occultation. The Shia Nizari Ismailis by definition have to have a present and living Imam until the end of time.[citation needed] Thus if any living Nizari Ismaili Imam fails to leave behind a successor after him then the Nizari Ismailism's cardinal principle would be broken and it's very raison d'etre would come to an end.

Who deny the concept of Occulation?
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A: Shia Nizari Ismailis

Problem: Translation:

The Arabs undertook large-scale efforts at translation. Having conquered the Greek world, they made Arabic versions of its philosophical and scientific works. During the Middle Ages, translations of some of these Arabic versions were made into Latin, chiefly at Cordoba in Spain. King Alfonso X el Sabio (Alphonse the Wise) of Castille in the 13th century promoted this effort by founding a Schola Traductorum (School of Translation) in Toledo. There Arabic texts, Hebrew texts, and Latin texts were translated into the other tongues by Muslim, Jewish and Christian scholars, who also argued the merits of their respective religions. Latin translations of Greek and original Arab works of scholarship and science helped advance European Scholasticism, and thus European science and culture.

When were some of the Arabic translations of earlier sentences translated into Latin?
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A:
Middle Ages