Problem: Police:

In 1566, the first police investigator of Rio de Janeiro was recruited. By the 17th century, most captaincies already had local units with law enforcement functions. On July 9, 1775 a Cavalry Regiment was created in the state of Minas Gerais for maintaining law and order. In 1808, the Portuguese royal family relocated to Brazil, because of the French invasion of Portugal. King João VI established the "Intendência Geral de Polícia" (General Police Intendancy) for investigations. He also created a Royal Police Guard for Rio de Janeiro in 1809. In 1831, after independence, each province started organizing its local "military police", with order maintenance tasks. The Federal Railroad Police was created in 1852.

When didn't Minas Gerais get a cavalry regiment?
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A: unanswerable


Problem: The Permian–Triassic extinction event, which was a prolonged event due to the accumulation of several extinction pulses, ended the dominance of the carnivores among the therapsids. In the early Triassic, all the medium to large land carnivore niches were taken over by archosaurs which, over an extended period of time (35 million years), came to include the crocodylomorphs, the pterosaurs, and the dinosaurs. By the Jurassic, the dinosaurs had come to dominate the large terrestrial herbivore niches as well.
What did the Jurassic period end?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1941, Reza Shah was forced to abdicate in favor of his son, Mohammad Reza Pahlavi, and established the Persian Corridor, a massive supply route that would last until the end of the ongoing war. The presence of so many foreign troops in the nation also culminated in the Soviet-backed establishment of two puppet regimes in the nation; the Azerbaijan People's Government, and the Republic of Mahabad. As the Soviet Union refused to relinquish the occupied Iranian territory, the Iran crisis of 1946 was followed, which particularly resulted in the dissolution of both puppet states, and the withdrawal of the Soviets.
Who succeeded Reza Shah after his abdication?
A: his son, Mohammad Reza Pahlavi


Context and question: Vacuum is useful in a variety of processes and devices. Its first widespread use was in the incandescent light bulb to protect the filament from chemical degradation. The chemical inertness produced by a vacuum is also useful for electron beam welding, cold welding, vacuum packing and vacuum frying. Ultra-high vacuum is used in the study of atomically clean substrates, as only a very good vacuum preserves atomic-scale clean surfaces for a reasonably long time (on the order of minutes to days). High to ultra-high vacuum removes the obstruction of air, allowing particle beams to deposit or remove materials without contamination. This is the principle behind chemical vapor deposition, physical vapor deposition, and dry etching which are essential to the fabrication of semiconductors and optical coatings, and to surface science. The reduction of convection provides the thermal insulation of thermos bottles. Deep vacuum lowers the boiling point of liquids and promotes low temperature outgassing which is used in freeze drying, adhesive preparation, distillation, metallurgy, and process purging. The electrical properties of vacuum make electron microscopes and vacuum tubes possible, including cathode ray tubes. The elimination of air friction is useful for flywheel energy storage and ultracentrifuges.
What are two things made possible by the electrical properties of vacuum?
Answer: electron microscopes and vacuum tubes


Question: Copyright infringement is reproducing, distributing, displaying or performing a work, or to make derivative works, without permission from the copyright holder, which is typically a publisher or other business representing or assigned by the work's creator. It is often called "piracy". While copyright is created the instance a work is fixed, generally the copyright holder can only get money damages if the owner registers the copyright.[citation needed] Enforcement of copyright is generally the responsibility of the copyright holder. The ACTA trade agreement, signed in May 2011 by the United States, Japan, Switzerland, and the EU, and which has not entered into force, requires that its parties add criminal penalties, including incarceration and fines, for copyright and trademark infringement, and obligated the parties to active police for infringement. There are limitations and exceptions to copyright, allowing limited use of copyrighted works, which does not constitute infringement. Examples of such doctrines are the fair use and fair dealing doctrine.
Is there an answer to this question: What countries refused to accept ACTA

Answer: unanswerable


Problem: FA Cup:

Following the 1914–15 edition, the competition was suspended due to the First World War, and didn't resume until 1919–20. The 1922–23 competition saw the first final to be played in the newly opened Wembley Stadium (known at the time as the Empire Stadium). Due to the outbreak of World War II, the competition wasn't played between the 1938–39 and 1945–46 editions. Due to the wartime breaks, the competition didn't celebrate its centenary year until 1980–81; fittingly the final featured a goal by Ricky Villa which was later voted the greatest goal ever scored at Wembley Stadium, but has since been replaced by Steven Gerrard.

When did Wembly stadium open? 
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A:
1922–23