Problem: Literature:

Poetry is a form of literary art which uses aesthetic and rhythmic qualities of language to evoke meanings in addition to, or in place of, prosaic ostensible meaning. Poetry has traditionally been distinguished from prose by its being set in verse;[a] prose is cast in sentences, poetry in lines; the syntax of prose is dictated by meaning, whereas that of poetry is held across metre or the visual aspects of the poem. Prior to the nineteenth century, poetry was commonly understood to be something set in metrical lines; accordingly, in 1658 a definition of poetry is "any kind of subject consisting of Rythm or Verses". Possibly as a result of Aristotle's influence (his Poetics), "poetry" before the nineteenth century was usually less a technical designation for verse than a normative category of fictive or rhetorical art. As a form it may pre-date literacy, with the earliest works being composed within and sustained by an oral tradition; hence it constitutes the earliest example of literature.

Until when was prose considered to need metrical lines?
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A: unanswerable


Problem: Light-emitting diode:

The structure of QD-LEDs used for the electrical-excitation scheme is similar to basic design of OLEDs. A layer of quantum dots is sandwiched between layers of electron-transporting and hole-transporting materials. An applied electric field causes electrons and holes to move into the quantum dot layer and recombine forming an exciton that excites a QD. This scheme is commonly studied for quantum dot display. The tunability of emission wavelengths and narrow bandwidth is also beneficial as excitation sources for fluorescence imaging. Fluorescence near-field scanning optical microscopy (NSOM) utilizing an integrated QD-LED has been demonstrated.

A Quantum Dot LED has been used in what?
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A: near-field scanning optical microscopy (NSOM)


Problem: Jehovah%27s Witnesses:

Doctrines of Jehovah's Witnesses are established by the Governing Body. The religion does not tolerate dissent over doctrines and practices; members who openly disagree with the religion's teachings are expelled and shunned. Witness publications strongly discourage followers from questioning doctrine and counsel received from the Governing Body, reasoning that it is to be trusted as part of "God's organization". It also warns members to "avoid independent thinking", claiming such thinking "was introduced by Satan the Devil" and would "cause division". Those who openly disagree with official teachings are condemned as "apostates" who are "mentally diseased".

What religion accommodates members who question its teachings?
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A: unanswerable


Problem: Paris:

As of 2013 the City of Paris had 1,570 hotels with 70,034 rooms, of which 55 were rated five-star, mostly belonging to international chains and mostly located close to the centre and the Champs-Élysées. Paris has long been famous for its grand hotels. The Hotel Meurice, opened for British travellers in 1817, was one of the first luxury hotels in Paris. The arrival of the railroads and the Paris Exposition of 1855 brought the first flood of tourists and the first modern grand hotels; the Hôtel du Louvre (now an antiques marketplace) in 1855; the Grand Hotel (now the Intercontinental LeGrand) in 1862; and the Hôtel Continental in 1878. The Hôtel Ritz on Place Vendôme opened in 1898, followed by the Hôtel Crillon in an 18th-century building on the Place de la Concorde in 1909; the Hotel Bristol on rue de Fabourg Saint-Honoré in 1925; and the Hotel George V in 1928.

How many hotels are in the City of Paris?
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A:
1,570