Problem: Avicenna:

As a teenager, he was greatly troubled by the Metaphysics of Aristotle, which he could not understand until he read al-Farabi's commentary on the work. For the next year and a half, he studied philosophy, in which he encountered greater obstacles. In such moments of baffled inquiry, he would leave his books, perform the requisite ablutions, then go to the mosque, and continue in prayer till light broke on his difficulties. Deep into the night, he would continue his studies, and even in his dreams problems would pursue him and work out their solution. Forty times, it is said, he read through the Metaphysics of Aristotle, till the words were imprinted on his memory; but their meaning was hopelessly obscure, until one day they found illumination, from the little commentary by Farabi, which he bought at a bookstall for the small sum of three dirhams. So great was his joy at the discovery, made with the help of a work from which he had expected only mystery, that he hastened to return thanks to God, and bestowed alms upon the poor.

How long did Avicenna teach philosophy?
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A: unanswerable


Problem: Frédéric Chopin:

In October 1810, six months after Fryderyk's birth, the family moved to Warsaw, where his father acquired a post teaching French at the Warsaw Lyceum, then housed in the Saxon Palace. Fryderyk lived with his family in the Palace grounds. The father played the flute and violin; the mother played the piano and gave lessons to boys in the boarding house that the Chopins kept. Chopin was of slight build, and even in early childhood was prone to illnesses.

When did Chopin's family move to Warsaw?
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A: October 1810


Problem: Valencia:

The city had surrendered without a fight to the invading Moors (Berbers and Arabs) by 714 AD, and the cathedral of Saint Vincent was turned into a mosque. Abd al-Rahman I, the first emir of Cordoba, ordered the city destroyed in 755 during his wars against other nobility, but several years later his son, Abdullah, had a form of autonomous rule over the province of Valencia. Among his administrative acts he ordered the building of a luxurious palace, the Russafa, on the outskirts of the city in the neighbourhood of the same name. So far no remains have been found. Also at this time Valencia received the name Medina al-Turab (City of Sand). When Islamic culture settled in, Valencia, then called Balansiyya, prospered from the 10th century, due to a booming trade in paper, silk, leather, ceramics, glass and silver-work. The architectural legacy of this period is abundant in Valencia and can still be appreciated today in the remnants of the old walls, the Baños del Almirante bath house, Portal de Valldigna street and even the Cathedral and the tower, El Micalet (El Miguelete), which was the minaret of the old mosque.

What feature of Valencia used to be a minaret?
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A: El Micalet


Problem: Raleigh, North Carolina:

Raleigh is home to a wide variety of religious practitioners. As of 2013, 46.41% of people in Raleigh are affiliated with a religion. The predominant religion in Raleigh is Christianity, with the largest numbers of adherents being Roman Catholic (11.3%), Baptist (10.85%), and Methodist (7.08%). Others include Presbyterian (2.52%), Pentecostal (1.99%), Episcopalian (1.12%), Lutheran (1.06%), Latter-Day Saints (0.99%), and other Christian denominations (6.68%) including Eastern Orthodox, Coptic Orthodox, Jehovah's Witness, Christian Science, Christian Unitarianism, other Mainline Protestant groups, and non-denominational.

What other denominations are there in Raleigh?
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A:
Eastern Orthodox, Coptic Orthodox, Jehovah's Witness,