Problem: Hard rock:

Emerging British acts included Free, who released their signature song "All Right Now" (1970), which has received extensive radio airplay in both the UK and US. After the breakup of the band in 1973, vocalist Paul Rodgers joined supergroup Bad Company, whose eponymous first album (1974) was an international hit. The mixture of hard rock and progressive rock, evident in the works of Deep Purple, was pursued more directly by bands like Uriah Heep and Argent. Scottish band Nazareth released their self-titled debut album in 1971, producing a blend of hard rock and pop that would culminate in their best selling, Hair of the Dog (1975), which contained the proto-power ballad "Love Hurts". Having enjoyed some national success in the early 1970s, Queen, after the release of Sheer Heart Attack (1974) and A Night at the Opera (1975), gained international recognition with a sound that used layered vocals and guitars and mixed hard rock with heavy metal, progressive rock, and even opera. The latter featured the single "Bohemian Rhapsody", which stayed at number one in the UK charts for nine weeks.

What band had the single Bohemian Rhapsody at number one on the US charts for nine weeks?
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A: unanswerable

Problem: Detroit, like many places in the United States, developed racial conflict and discrimination in the 20th century following rapid demographic changes as hundreds of thousands of new workers were attracted to the industrial city; in a short period it became the 4th-largest city in the nation. The Great Migration brought rural blacks from the South; they were outnumbered by southern whites who also migrated to the city. Immigration brought southern and eastern Europeans of Catholic and Jewish faith; these new groups competed with native-born whites for jobs and housing in the booming city. Detroit was one of the major Midwest cities that was a site for the dramatic urban revival of the Ku Klux Klan beginning in 1915. "By the 1920s the city had become a stronghold of the KKK," whose members opposed Catholic and Jewish immigrants, as well as black Americans. The Black Legion, a secret vigilante group, was active in the Detroit area in the 1930s, when one-third of its estimated 20,000 to 30,000 members in Michigan were based in the city. It was defeated after numerous prosecutions following the kidnapping and murder in 1936 of Charles Poole, a Catholic Works Progress Administration organizer. A total of 49 men of the Black Legion were convicted of numerous crimes, with many sentenced to life in prison for murder.
By which decade had the KKK become very active in Detroit?
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Answer: 1920s

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
To this day, most hunter-gatherers have a symbolically structured sexual division of labour. However, it is true that in a small minority of cases, women hunt the same kind of quarry as men, sometimes doing so alongside men. The best-known example are the Aeta people of the Philippines. According to one study, "About 85% of Philippine Aeta women hunt, and they hunt the same quarry as men. Aeta women hunt in groups and with dogs, and have a 31% success rate as opposed to 17% for men. Their rates are even better when they combine forces with men: mixed hunting groups have a full 41% success rate among the Aeta." Among the Ju'/hoansi people of Namibia, women help men track down quarry. Women in the Australian Martu also primarily hunt small animals like lizards to feed their children and maintain relations with other women.
Men in the Austrailian Martu primarily hunt small animals like what?
A: unanswerable

Context and question: At the end of the Second World War, Canada possessed the fourth-largest air force and fifth-largest naval surface fleet in the world, as well as the largest volunteer army ever fielded. Conscription for overseas service was introduced only near the end of the war, and only 2,400 conscripts actually made it into battle. Originally, Canada was thought to have had the third-largest navy in the world, but with the fall of the Soviet Union, new data based on Japanese and Soviet sources found that to be incorrect.
What was introduced at then end of the war?
Answer: unanswerable

Question: The Atlantic Ocean has less influence on the climate of the Piedmont region, which has hotter summers and colder winters than in the coast. Daytime highs in the Piedmont often reach over 90 F (32 C) in the summer. While it is not common for the temperature to reach over 100 F (38 C) in the state, such temperatures, when they occur, typically are found only in the lower-elevation areas of the Piedmont and far-inland areas of the coastal plain. The weaker influence of the Atlantic Ocean also means that temperatures in the Piedmont often fluctuate more widely than in the coast.
Is there an answer to this question: What type of influence of the Atlantic Ocean makes the temperatures fluctuate more than on the coast?

Answer: weaker

Question: World War II (1939-1945) devastated the country's economy, but the high levels of economic growth that followed from 1950 to 1980 have been called the Greek economic miracle. From 2000 Greece saw high levels of GDP growth above the Eurozone average, peaking at 5.8% in 2003 and 5.7% in 2006. The subsequent Great Recession and Greek government-debt crisis, a central focus of the wider European debt crisis, plunged the economy into a sharp downturn, with real GDP growth rates of 0.3% in 2008, 4.3% in 2009, 5.5% in 2010, 9.1% in 2011, 7.3% in 2012 and 3.2% in 2013. In 2011, the country's public debt reached 356 billion (172% of nominal GDP). After negotiating the biggest debt restructuring in history with the private sector, Greece reduced its sovereign debt burden to 280 billion (137% of GDP) in the first quarter of 2012. Greece achieved a real GDP growth rate of 0.7% in 2014 after 6 years of economic decline, but fell back into recession in 2015.
Is there an answer to this question: What year did Greece fall back into recession?

Answer:
2015