Problem: Eton College:

The current "Precentor" (Head of Music) is Tim Johnson, and the School boasts eight organs and an entire building for music (performance spaces include the School Hall, the Farrer Theatre and two halls dedicated to music, the Parry Hall and the Concert Hall). Many instruments are taught, including obscure ones such as the didgeridoo. The School participates in many national competitions; many pupils are part of the National Youth Orchestra, and the School gives scholarships for dedicated and talented musicians. A former Precentor of the college, Ralph Allwood set up and organised Eton Choral Courses, which run at the School every summer.

Who currently guides the National Youth Orchestra?
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A: unanswerable

Problem: The Columbia Encyclopedia distinguishes between the Yuan dynasty and the other Mongol Empire khanates of Ilkhanate, Chagatai Khanate and the Golden Horde. It describes the Yuan dynasty as "A Mongol dynasty of China that ruled from 1271 to 1368, and a division of the great empire conquered by the Mongols. Founded by Kublai Khan, who adopted the Chinese dynastic name of Yuan in 1271." The Encyclopedia Americana describes the Yuan dynasty as "the line of Mongol rulers in China" and adds that the Mongols "proclaimed a Chinese-style Yuan dynasty at Khanbaliq (Beijing)." The Metropolitan Museum of Art writes that the Mongol rulers of the Yuan dynasty "adopted Chinese political and cultural models; ruling from their capitals in Dadu, they assumed the role of Chinese emperors," although Tibetologist Thomas Laird dismissed the Yuan dynasty as a non-Chinese polity and plays down its Chinese characteristics. The Metropolitan Museum of Art also noted that in spite of the gradual assimilation of Yuan monarchs, the Mongol rulers largely ignored the literati and imposed harsh policies discriminating against southern Chinese. In his Kublai Khan: His Life and Times, Rossabi explains that Kublai "created government institutions that either resembled or were the same as the traditional Chinese ones", and he "wished to signal to the Chinese that he intended to adopt the trappings and style of a Chinese ruler".
What did Thomas Laird dismiss the Yuan dynasty as?
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Answer: a non-Chinese polity

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Later, von Neumann suggested a new method of linear programming, using the homogeneous linear system of Gordan (1873), which was later popularized by Karmarkar's algorithm. Von Neumann's method used a pivoting algorithm between simplices, with the pivoting decision determined by a nonnegative least squares subproblem with a convexity constraint (projecting the zero-vector onto the convex hull of the active simplex). Von Neumann's algorithm was the first interior point method of linear programming.
What was the new method of linear programming that von Neumann suggested?
A: homogeneous linear system of Gordan

Context and question: On 25 February 1991, the Warsaw Pact was declared disbanded at a meeting of defense and foreign ministers from remaining Pact countries meeting in Hungary. On 1 July 1991, in Prague, the Czechoslovak President Vaclav Havel formally ended the 1955 Warsaw Treaty Organization of Friendship, Cooperation, and Mutual Assistance and so disestablished the Warsaw Treaty after 36 years of military alliance with the USSR. In fact, the treaty was de facto disbanded in December 1989 during the violent revolution in Romania, which toppled the communist government, without military intervention form other member states. The USSR disestablished itself in December 1991.
In which country did Warsaw Pact officials meet to dissolve the alliance?
Answer: Hungary

Question: After the death of the replacement bishop Gregory in 345, Constans used his influence to allow Athanasius to return to Alexandria in October 345, amidst the enthusiastic demonstrations of the populace. This began a "golden decade" of peace and prosperity, during which time Athanasius assembled several documents relating to his exiles and returns from exile in the Apology Against the Arians. However, upon Constans's death in 350, another civil war broke out, which left pro-Arian Constantius as sole emperor. An Alexandria local council in 350 replaced (or reaffirmed) Athanasius in his see.
Is there an answer to this question: Who did he have to thank for his ability to come back to Alexandria in 345?

Answer: Constans

Question: The first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type doping of GaN. Nakamura, Akasaki and Amano were awarded the 2014 Nobel prize in physics for their work. In 1995, Alberto Barbieri at the Cardiff University Laboratory (GB) investigated the efficiency and reliability of high-brightness LEDs and demonstrated a "transparent contact" LED using indium tin oxide (ITO) on (AlGaInP/GaAs).
Is there an answer to this question: What did Nakamura, Akasaki, and Amano receive for their work?

Answer:
2014 Nobel prize in physics