Problem: Palermo:

The cathedral has a heliometer (solar "observatory") of 1690, one of a number built in Italy in the 17th and 18th centuries. The device itself is quite simple: a tiny hole in one of the minor domes acts as pinhole camera, projecting an image of the sun onto the floor at solar noon (12:00 in winter, 13:00 in summer). There is a bronze line, la Meridiana on the floor, running precisely N/S. The ends of the line mark the positions as at the summer and winter solstices; signs of the zodiac show the various other dates throughout the year.

What has lunar observatory built in 1690?
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A: unanswerable


Problem: Greeks:

The history of the Greek people is closely associated with the history of Greece, Cyprus, Constantinople, Asia Minor and the Black Sea. During the Ottoman rule of Greece, a number of Greek enclaves around the Mediterranean were cut off from the core, notably in Southern Italy, the Caucasus, Syria and Egypt. By the early 20th century, over half of the overall Greek-speaking population was settled in Asia Minor (now Turkey), while later that century a huge wave of migration to the United States, Australia, Canada and elsewhere created the modern Greek diaspora.

What has lead to the current situation of vast dispersion of the French people?
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A: unanswerable


Problem: Saint Helena:

Saint Helena has the international calling code +290 which, since 2006, Tristan da Cunha shares. Saint Helena telephone numbers changed from 4 to 5 digits on 1 October 2013 by being prefixed with the digit "2", i.e. 2xxxx, with the range 5xxxx being reserved for mobile numbering, and 8xxx being used for Tristan da Cunha numbers (these still shown as 4 digits).

Who shares the calling code +290 with Saint Helena?
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A: Tristan da Cunha


Problem: Middle Ages:

The breakup of the Carolingian Empire was accompanied by invasions, migrations, and raids by external foes. The Atlantic and northern shores were harassed by the Vikings, who also raided the British Isles and settled there as well as in Iceland. In 911, the Viking chieftain Rollo (d. c. 931) received permission from the Frankish King Charles the Simple (r. 898–922) to settle in what became Normandy.[Q] The eastern parts of the Frankish kingdoms, especially Germany and Italy, were under continual Magyar assault until the invader's defeat at the Battle of Lechfeld in 955. The breakup of the Abbasid dynasty meant that the Islamic world fragmented into smaller political states, some of which began expanding into Italy and Sicily, as well as over the Pyrenees into the southern parts of the Frankish kingdoms.

In what year did the Battle of Lechfeld occur?
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A:
955