Problem: North Carolina:

Every year the Appalachian Mountains attract several million tourists to the Western part of the state, including the historic Biltmore Estate. The scenic Blue Ridge Parkway and Great Smoky Mountains National Park are the two most visited national park and unit in the United States with over 25 million visitors in 2013. The City of Asheville is consistently voted as one of the top places to visit and live in the United States, known for its rich art deco architecture, mountain scenery and outdoor activities, and liberal and happy residents.

What North Carolina City is consistently voted one of the top places to live in the United States?
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A: Asheville


Problem: The Eastern Han, also known as the Later Han, formally began on 5 August 25, when Liu Xiu became Emperor Guangwu of Han. During the widespread rebellion against Wang Mang, the state of Goguryeo was free to raid Han's Korean commanderies; Han did not reaffirm its control over the region until AD 30. The Trưng Sisters of Vietnam rebelled against Han in AD 40. Their rebellion was crushed by Han general Ma Yuan (d. AD 49) in a campaign from AD 42–43. Wang Mang renewed hostilities against the Xiongnu, who were estranged from Han until their leader Bi (比), a rival claimant to the throne against his cousin Punu (蒲奴), submitted to Han as a tributary vassal in AD 50. This created two rival Xiongnu states: the Southern Xiongnu led by Bi, an ally of Han, and the Northern Xiongnu led by Punu, an enemy of Han.
Which state raided Han's Korean commanderies?
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Answer: Goguryeo


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
New York's airspace is the busiest in the United States and one of the world's busiest air transportation corridors. The three busiest airports in the New York metropolitan area include John F. Kennedy International Airport, Newark Liberty International Airport, and LaGuardia Airport; 109 million travelers used these three airports in 2012, and the city's airspace is the busiest in the nation. JFK and Newark Liberty were the busiest and fourth busiest U.S. gateways for international air passengers, respectively, in 2012; as of 2011, JFK was the busiest airport for international passengers in North America. Plans have advanced to expand passenger volume at a fourth airport, Stewart International Airport near Newburgh, New York, by the Port Authority of New York and New Jersey. Plans were announced in July 2015 to entirely rebuild LaGuardia Airport in a multibillion-dollar project to replace its aging facilities.
What is the second busiest airport in the New York metro area?
A: Newark Liberty International Airport


Context and question: Machine vision systems often require bright and homogeneous illumination, so features of interest are easier to process. LEDs are often used for this purpose, and this is likely to remain one of their major uses until the price drops low enough to make signaling and illumination uses more widespread. Barcode scanners are the most common example of machine vision, and many low cost products use red LEDs instead of lasers. Optical computer mice are an example of LEDs in machine vision, as it is used to provide an even light source on the surface for the miniature camera within the mouse. LEDs constitute a nearly ideal light source for machine vision systems for several reasons:
 What is the most uncommon example of a machine vision system?
Answer: unanswerable


Question: Tito was interred in a mausoleum in Belgrade, which forms part of a memorial complex in the grounds of the Museum of Yugoslav History (formerly called "Museum 25 May" and "Museum of the Revolution"). The actual mausoleum is called House of Flowers (Kuća Cveća) and numerous people visit the place as a shrine to "better times". The museum keeps the gifts Tito received during his presidency. The collection also includes original prints of Los Caprichos by Francisco Goya, and many others. The Government of Serbia has planned to merge it into the Museum of the History of Serbia. At the time of his death, speculation began about whether his successors could continue to hold Yugoslavia together. Ethnic divisions and conflict grew and eventually erupted in a series of Yugoslav wars a decade after his death.
Is there an answer to this question: In what city was Tito interred?

Answer: Belgrade


Problem: Cubism:

In their theoretical rules, the Cubist architects expressed the requirement of dynamism, which would surmount the matter and calm contained in it, through a creative idea, so that the result would evoke feelings of dynamism and expressive plasticity in the viewer. This should be achieved by shapes derived from pyramids, cubes and prisms, by arrangements and compositions of oblique surfaces, mainly triangular, sculpted facades in protruding crystal-like units, reminiscent of the so-called diamond cut, or even cavernous that are reminiscent of the late Gothic architecture. In this way, the entire surfaces of the facades including even the gables and dormers are sculpted. The grilles as well as other architectural ornaments attain a three-dimensional form. Thus, new forms of windows and doors were also created, e. g. hexagonal windows. Czech Cubist architects also designed Cubist furniture.

What's  window shapes di Czech Cubist architects use? 
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A:
hexagonal