Problem: PlayStation 3:

Sony officially unveiled PlayStation 3 (then marketed as PLAYSTATION 3) to the public on May 16, 2005, at E3 2005, along with a 'boomerang' shaped prototype design of the Sixaxis controller. A functional version of the system was not present there, nor at the Tokyo Game Show in September 2005, although demonstrations (such as Metal Gear Solid 4: Guns of the Patriots) were held at both events on software development kits and comparable personal computer hardware. Video footage based on the predicted PlayStation 3 specifications was also shown (notably a Final Fantasy VII tech demo).

What event did Microsoft choose for the PS3 unveiling?
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A: unanswerable


Problem: Napoleon married Joséphine de Beauharnais in 1796, when he was 26; she was a 32-year-old widow whose first husband had been executed during the Revolution. Until she met Bonaparte, she had been known as "Rose", a name which he disliked. He called her "Joséphine" instead, and she went by this name henceforth. Bonaparte often sent her love letters while on his campaigns. He formally adopted her son Eugène and cousin Stéphanie and arranged dynastic marriages for them. Joséphine had her daughter Hortense marry Napoleon's brother Louis.
In what year did Napoleon marry Joséphine de Beauharnais?
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Answer: 1796


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The university operates under 11 colleges or schools, which collectively offer 194 bachelor's degree programs, 68 master's degree programs, 25 PhD programs, and a Juris Doctor program. BYU also manages some courses and majors through the David M. Kennedy Center for International Studies and "miscellaneous" college departments, including Undergraduate Education, Graduate Studies, Independent Study, Continuing Education, and the Honors Program. BYU's Winter semester ends earlier than most universities in April since there is no Spring break, thus allowing students to pursue internships and other summer activities earlier. A typical academic year is broken up into two semesters: Fall (September–December) and Winter (January–April), as well as two shorter terms during the summer months: Spring (May–June) and Summer (July–August).
When is spring break for Brigham Young University?
A: unanswerable


Context and question: In the mid 17th century, after the English Civil War (1642–1651), Parliament strengthened its position relative to the monarch then gained more power through the Glorious Revolution of 1688 and passage of the Bill of Rights in 1689. The monarch could no longer establish any law or impose any tax without its permission and thus the House of Commons became a part of the government. It is at this point that a modern style of prime minister begins to emerge.
What bill gave the monarch the power to establish law and impose taxes?
Answer: unanswerable


Question: DC systems (especially third-rail systems) are limited to relatively low voltages and this can limit the size and speed of trains and cannot use low-level platform and also limit the amount of air-conditioning that the trains can provide. This may be a factor favouring overhead wires and high-voltage AC, even for urban usage. In practice, the top speed of trains on third-rail systems is limited to 100 mph (160 km/h) because above that speed reliable contact between the shoe and the rail cannot be maintained.
Is there an answer to this question: What is the speed limit for third rail system trains?

Answer: 160 km/h


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The city of Bern or Berne (German: Bern, pronounced [bɛrn] ( listen); French: Berne [bɛʁn]; Italian: Berna [ˈbɛrna]; Romansh: Berna  [ˈbɛrnɐ] (help·info); Bernese German: Bärn [b̥æːrn]) is the de facto capital of Switzerland, referred to by the Swiss as their (e.g. in German) Bundesstadt, or "federal city".[note 1] With a population of 140,634 (November 2015), Bern is the fifth most populous city in Switzerland. The Bern agglomeration, which includes 36 municipalities, had a population of 406,900 in 2014. The metropolitan area had a population of 660,000 in 2000. Bern is also the capital of the Canton of Bern, the second most populous of Switzerland's cantons.
Where does Bern rank in population in Switzerland?
A:
second