Problem: Incandescent light bulb:

In addressing the question of who invented the incandescent lamp, historians Robert Friedel and Paul Israel list 22 inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. They conclude that Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve (by use of the Sprengel pump) and a high resistance that made power distribution from a centralized source economically viable.

Which three historians wrote the conclusion that Edison's version was more viable than other early versions?
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A: unanswerable

Problem: Buckingham Palace:

Court presentations of aristocratic young ladies to the monarch took place at the palace from the reign of Edward VII. These young women were known as debutantes, and the occasiontermed their "coming out"represented their first entree into society. Debutantes wore full court dress, with three tall ostrich feathers in their hair. They entered, curtsied, and performed a choreographed backwards walk and a further curtsy, while manoeuvring a dress train of prescribed length. (The ceremony, known as an evening court, corresponded to the "court drawing rooms" of Victoria's reign.) After World War II, the ceremony was replaced by less formal afternoon receptions, usually without choreographed curtsies and court dress.

What was the name for the ceremony where debutantes had their first introduction into society?
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A: coming out

Problem: Mosaic:

Another great undertaking by Constantine Monomachos was the restoration of the Church of the Holy Sepulchre in Jerusalem between 1042 and 1048. Nothing survived of the mosaics which covered the walls and the dome of the edifice but the Russian abbot Daniel, who visited Jerusalem in 11061107 left a description: "Lively mosaics of the holy prophets are under the ceiling, over the tribune. The altar is surmounted by a mosaic image of Christ. In the main altar one can see the mosaic of the Exhaltation of Adam. In the apse the Ascension of Christ. The Annunciation occupies the two pillars next to the altar."

What survives of the mosaics that adorned the walls and dome of the Church of the Holy Sepulchre?
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A: Nothing

Problem: Tajikistan:

Tajikistan means the "Land of the Tajiks". The suffix "-stan" (Persian: -stan) is Persian for "place of" or "country" and Tajik is, most likely, the name of a pre-Islamic (before the seventh century A.D.) tribe. According to the Library of Congress's 1997 Country Study of Tajikistan, it is difficult to definitively state the origins of the word "Tajik" because the term is "embroiled in twentieth-century political disputes about whether Turkic or Iranian peoples were the original inhabitants of Central Asia."

What is most likely the name of a pre-Indian tribe?
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A:
unanswerable