Problem: Queen (band):

In July 1973, Queen finally under a Trident/EMI deal released their eponymous debut album, an effort influenced by the heavy metal and progressive rock of the day. The album was received well by critics; Gordon Fletcher of Rolling Stone said "their debut album is superb", and Chicago's Daily Herald called it an "above average debut". It drew little mainstream attention, and the lead single "Keep Yourself Alive", a Brian May composition, sold poorly. Retrospectively, "Keep Yourself Alive" is cited as the highlight of the album, and in 2008 Rolling Stone ranked it 31st in the "100 Greatest Guitar Songs of All Time", describing it as "an entire album's worth of riffs crammed into a single song". The album was certified gold in the UK and the US.

In what year was Queen's first album released?
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A: 1973

Problem: Zinc:

64Zn, the most abundant isotope of zinc, is very susceptible to neutron activation, being transmuted into the highly radioactive 65Zn, which has a half-life of 244 days and produces intense gamma radiation. Because of this, Zinc Oxide used in nuclear reactors as an anti-corrosion agent is depleted of 64Zn before use, this is called depleted zinc oxide. For the same reason, zinc has been proposed as a salting material for nuclear weapons (cobalt is another, better-known salting material). A jacket of isotopically enriched 64Zn would be irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, forming a large amount of 65Zn significantly increasing the radioactivity of the weapon's fallout. Such a weapon is not known to have ever been built, tested, or used. 65Zn is also used as a tracer to study how alloys that contain zinc wear out, or the path and the role of zinc in organisms.

What is used to study how alloys containing zinc melt?
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A: unanswerable

Problem: Nigeria:

Nigeria was ranked 30th in the world in terms of GDP (PPP) in 2012. Nigeria is the United States' largest trading partner in sub-Saharan Africa and supplies a fifth of its oil (11% of oil imports). It has the seventh-largest trade surplus with the US of any country worldwide. Nigeria is the 50th-largest export market for US goods and the 14th-largest exporter of goods to the US. The United States is the country's largest foreign investor. The International Monetary Fund (IMF) projected economic growth of 9% in 2008 and 8.3% in 2009. The IMF further projects an 8% growth in the Nigerian economy in 2011.

How much of the US's oil comes from Nigeria?
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A: a fifth

Problem: United States presidential election, 2004:

At the invitation of the United States government, the Organization for Security and Cooperation in Europe (OSCE) sent a team of observers to monitor the presidential elections in 2004. It was the first time the OSCE had sent observers to a U.S. presidential election, although they had been invited in the past. In September 2004 the OSCE issued a report on U.S. electoral processes and the election final report. The report reads: "The November 2, 2004 elections in the United States mostly met the OSCE commitments included in the 1990 Copenhagen Document. They were conducted in an environment that reflects a long-standing democratic tradition, including institutions governed by the rule of law, free and generally professional media, and a civil society intensively engaged in the election process. There was exceptional public interest in the two leading presidential candidates and the issues raised by their respective campaigns, as well as in the election process itself."

Why did OSCE come to the US in 1990?
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A:
unanswerable