Problem: Infrared:

Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space, such as molecular clouds; detect objects such as planets, and to view highly red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatus.

What technology allows infrared thermal imaging cameras to observe people or animals without being detected?
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A: unanswerable


Problem: The Bronx's evolution from a hot bed of Latin jazz to an incubator of hip hop was the subject of an award-winning documentary, produced by City Lore and broadcast on PBS in 2006, "From Mambo to Hip Hop: A South Bronx Tale". Hip Hop first emerged in the South Bronx in the early 1970s. The New York Times has identified 1520 Sedgwick Avenue "an otherwise unremarkable high-rise just north of the Cross Bronx Expressway and hard along the Major Deegan Expressway" as a starting point, where DJ Kool Herc presided over parties in the community room.
Where is 1520 Sedgwick?
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Answer: just north of the Cross Bronx Expressway and hard along the Major Deegan Expressway


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The library system of the university is divided between the main library and each of the colleges and schools. The main building is the 14-story Theodore M. Hesburgh Library, completed in 1963, which is the third building to house the main collection of books. The front of the library is adorned with the Word of Life mural designed by artist Millard Sheets. This mural is popularly known as "Touchdown Jesus" because of its proximity to Notre Dame Stadium and Jesus' arms appearing to make the signal for a touchdown.
In what year was the Theodore M. Hesburgh Library at Notre Dame finished?
A: 1963


Context and question: The palace measures 108 metres (354 ft) by 120 metres (390 ft), is 24 metres (79 ft) high and contains over 77,000 m2 (830,000 sq ft) of floorspace. The floor area is smaller than the Royal Palace of Madrid, the Papal Palace in Rome, the Louvre in Paris, the Hofburg Palace in Vienna, or the Forbidden City. There are 775 rooms, including 19 state rooms, 52 principal bedrooms, 188 staff bedrooms, 92 offices, and 78 bathrooms. The principal rooms are contained on the piano nobile behind the west-facing garden façade at the rear of the palace. The centre of this ornate suite of state rooms is the Music Room, its large bow the dominant feature of the façade. Flanking the Music Room are the Blue and the White Drawing Rooms. At the centre of the suite, serving as a corridor to link the state rooms, is the Picture Gallery, which is top-lit and 55 yards (50 m) long. The Gallery is hung with numerous works including some by Rembrandt, van Dyck, Rubens and Vermeer; other rooms leading from the Picture Gallery are the Throne Room and the Green Drawing Room. The Green Drawing Room serves as a huge anteroom to the Throne Room, and is part of the ceremonial route to the throne from the Guard Room at the top of the Grand Staircase. The Guard Room contains white marble statues of Queen Victoria and Prince Albert, in Roman costume, set in a tribune lined with tapestries. These very formal rooms are used only for ceremonial and official entertaining, but are open to the public every summer.
Which stateroom has a small bow as a feature of the facade?
Answer: unanswerable


Question: The event of the Protestant Reformation and the politics that ensued has been cited as the origins of German identity that arose in response to the spread of a common German language and literature. Early German national culture was developed through literary and religious figures including Martin Luther, Johann Wolfgang von Goethe and Friedrich Schiller. The concept of a German nation was developed by German philosopher Johann Gottfried Herder. The popularity of German identity arose in the aftermath of the French Revolution.
Is there an answer to this question: What concept was developed by Martin Luther?

Answer: 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