Problem: Hydrogen:

The first non-stop transatlantic crossing was made by the British airship R34 in 1919. Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H2 was used in the Hindenburg airship, which was destroyed in a midair fire over New Jersey on 6 May 1937. The incident was broadcast live on radio and filmed. Ignition of leaking hydrogen is widely assumed to be the cause, but later investigations pointed to the ignition of the aluminized fabric coating by static electricity. But the damage to hydrogen's reputation as a lifting gas was already done.

What year did the airship get destroyed?
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A: 1937


Problem: Steven Spielberg:

A strong consistent theme in his family-friendly work is a childlike, even naïve, sense of wonder and faith, as attested by works such as Close Encounters of the Third Kind, E.T. the Extra-Terrestrial, Hook, A.I. Artificial Intelligence and The BFG. According to Warren Buckland, these themes are portrayed through the use of low height camera tracking shots, which have become one of Spielberg's directing trademarks. In the cases when his films include children (E.T. the Extra-Terrestrial, Empire of the Sun, Jurassic Park, etc.), this type of shot is more apparent, but it is also used in films like Munich, Saving Private Ryan, The Terminal, Minority Report, and Amistad. If one views each of his films, one will see this shot utilized by the director, notably the water scenes in Jaws are filmed from the low-angle perspective of someone swimming. Another child oriented theme in Spielberg's films is that of loss of innocence and coming-of-age. In Empire of the Sun, Jim, a well-groomed and spoiled English youth, loses his innocence as he suffers through World War II China. Similarly, in Catch Me If You Can, Frank naively and foolishly believes that he can reclaim his shattered family if he accumulates enough money to support them.

Who wrote Empire of the Sun?
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A: unanswerable


Problem: Frédéric Chopin:

Chopin's études are largely in straightforward ternary form. He used them to teach his own technique of piano playing—for instance playing double thirds (Op. 25, No. 6), playing in octaves (Op. 25, No. 10), and playing repeated notes (Op. 10, No.  7).

What pieces of his did Chopin use to teach his technique?
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A: études


Problem: IBM:

In 2012, Fortune ranked IBM the second largest U.S. firm in terms of number of employees (435,000 worldwide), the fourth largest in terms of market capitalization, the ninth most profitable, and the nineteenth largest firm in terms of revenue. Globally, the company was ranked the 31st largest in terms of revenue by Forbes for 2011. Other rankings for 2011/2012 include №1 company for leaders (Fortune), №1 green company in the United States (Newsweek), №2 best global brand (Interbrand), №2 most respected company (Barron's), №5 most admired company (Fortune), and №18 most innovative company (Fast Company).

What rank did Forbes have in terms of revenue in 2012?
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A:
unanswerable