Problem: Compact disc:

In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide. CDs are increasingly being replaced by other forms of digital storage and distribution, with the result that audio CD sales rates in the U.S. have dropped about 50% from their peak; however, they remain one of the primary distribution methods for the music industry. In 2014, revenues from digital music services matched those from physical format sales for the first time.

In what year did CD sales peak?
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A: unanswerable


Problem: When revolutionary France declared war on Great Britain in 1793, the United States sought to remain neutral, but the Jay Treaty, which was favorable to Great Britain, angered the French government, which viewed it as a violation of the 1778 Treaty of Alliance. French privateers began to seize U.S. vessels, which led to an undeclared "Quasi-War" between the two nations. Fought at sea from 1798 to 1800, the United States won a string of victories in the Caribbean. George Washington was called out of retirement to head a "provisional army" in case of invasion by France, but President John Adams managed to negotiate a truce, in which France agreed to terminate the prior alliance and cease its attacks.
Where did US ships and French privateers fight between 1798 and 1800?
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Answer: the Caribbean


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Two Polish friends in Paris were also to play important roles in Chopin's life there. His fellow student at the Warsaw Conservatory, Julian Fontana, had originally tried unsuccessfully to establish himself in England; Albert Grzymała, who in Paris became a wealthy financier and society figure, often acted as Chopin's adviser and "gradually began to fill the role of elder brother in [his] life." Fontana was to become, in the words of Michałowski and Samson, Chopin's "general factotum and copyist".
Julian Fontana tried to find his way where before moving to Paris?
A: England


Context and question: PS3 was given the number-eight spot on PC World magazine's list of "The Top 21 Tech Screwups of 2006", where it was criticized for being "Late, Expensive and Incompatible". GamesRadar ranked PS3 as the top item in a feature on game-related PR disasters, asking how Sony managed to "take one of the most anticipated game systems of all time and — within the space of a year — turn it into a hate object reviled by the entire internet", but added that despite its problems the system has "untapped potential". Business Week summed up the general opinion by stating that it was "more impressed with what [the PlayStation 3] could do than with what it currently does".
What list by PC World ranked PlayStation ninth, in a bad way?
Answer: unanswerable


Question: In Anglo-American academic political philosophy, the publication of John Rawls's A Theory of Justice in 1971 is considered a milestone. Rawls used a thought experiment, the original position, in which representative parties choose principles of justice for the basic structure of society from behind a veil of ignorance. Rawls also offered a criticism of utilitarian approaches to questions of political justice. Robert Nozick's 1974 book Anarchy, State, and Utopia, which won a National Book Award, responded to Rawls from a libertarian perspective and gained academic respectability for libertarian viewpoints.
Is there an answer to this question: What did John Rawls write in 1974?

Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
London is one of the leading tourist destinations in the world and in 2015 was ranked as the most visited city in the world with over 65 million visits. It is also the top city in the world by visitor cross-border spending, estimated at US$20.23 billion in 2015 Tourism is one of London's prime industries, employing the equivalent of 350,000 full-time workers in 2003, and the city accounts for 54% of all inbound visitor spend in UK. As of 2016 London is rated as the world top ranked city destination by TripAdvisor users.
What percentage of visitor money is estimated to be spent in London?
A:
54%