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

Problem: Hard rock is a form of loud, aggressive rock music. The electric guitar is often emphasised, used with distortion and other effects, both as a rhythm instrument using repetitive riffs with a varying degree of complexity, and as a solo lead instrument. Drumming characteristically focuses on driving rhythms, strong bass drum and a backbeat on snare, sometimes using cymbals for emphasis. The bass guitar works in conjunction with the drums, occasionally playing riffs, but usually providing a backing for the rhythm and lead guitars. Vocals are often growling, raspy, or involve screaming or wailing, sometimes in a high range, or even falsetto voice.
Rhythm guitar in hard rock usually plays what?
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Answer: repetitive riffs with a varying degree of complexity

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Hunter-gathering lifestyles remained prevalent in some parts of the New World, Sub-Saharan Africa, and Siberia, as well as all of Australia, until the European Age of Discovery. They still persist in some tribal societies, albeit in rapid decline. Peoples that preserved paleolithic hunting-gathering until the recent past include some indigenous peoples of the Amazonas (Ache), some Central and Southern African (San people), some peoples of New Guinea (Fayu), the Mlabri of Thailand and Laos, the Vedda people of Sri Lanka, and a handful of uncontacted peoples. In Africa, the only remaining full-time hunter-gatherers are the Hadza of Tanzania.[citation needed]
Where does the hunter-gathering lifestyle persist, though in decline?
A: some tribal societies

Context and question: Through 2010, the party improved its vote in the Tasmanian and South Australian state elections and achieved state government in Victoria. In March 2011, the New South Wales Liberal-National Coalition led by Barry O'Farrell won government with the largest election victory in post-war Australian history at the State Election. In Queensland, the Liberal and National parties merged in 2008 to form the new Liberal National Party of Queensland (registered as the Queensland Division of the Liberal Party of Australia). In March 2012, the new party achieved Government in an historic landslide, led by former Brisbane Lord Mayor, Campbell Newman.
Who led the new Liberal National Party of Queensland through the election in March 2010?
Answer: unanswerable

Question: Archaeologists excavating near the city have unearthed Iron Age sites that may date from 500 BCE. The region comprising modern Hyderabad and its surroundings was known as Golkonda (Golla Konda-"shepherd's hill"), and was ruled by the Chalukya dynasty from 624 CE to 1075 CE. Following the dissolution of the Chalukya empire into four parts in the 11th century, Golkonda came under the control of the Kakatiya dynasty from 1158, whose seat of power was at Warangal, 148 km (92 mi) northeast of modern Hyderabad.
Is there an answer to this question: When did the Calukya empire split into four?

Answer: the 11th century

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Natural uranium consists of three major isotopes: uranium-238 (99.28% natural abundance), uranium-235 (0.71%), and uranium-234 (0.0054%). All three are radioactive, emitting alpha particles, with the exception that all three of these isotopes have small probabilities of undergoing spontaneous fission, rather than alpha emission. There are also five other trace isotopes: uranium-239, which is formed when 238U undergoes spontaneous fission, releasing neutrons that are captured by another 238U atom; uranium-237, which is formed when 238U captures a neutron but emits two more, which then decays to neptunium-237; uranium-233, which is formed in the decay chain of that neptunium-237; and finally, uranium-236 and -240, which appear in the decay chain of primordial plutonium-244. It is also expected that thorium-232 should be able to undergo double beta decay, which would produce uranium-232, but this has not yet been observed experimentally.
When uranium isotope is formed from the decay of neptunium-237?
A:
uranium-233