Problem: Vacuum:

The lowest pressure that can be attained in a system is also dependent on many things other than the nature of the pumps. Multiple pumps may be connected in series, called stages, to achieve higher vacuums. The choice of seals, chamber geometry, materials, and pump-down procedures will all have an impact. Collectively, these are called vacuum technique. And sometimes, the final pressure is not the only relevant characteristic. Pumping systems differ in oil contamination, vibration, preferential pumping of certain gases, pump-down speeds, intermittent duty cycle, reliability, or tolerance to high leakage rates.

How do leakage rates usually happen?
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A: unanswerable

Problem: In addition to such annual festivals like Calle Ocho Festival and Carnaval Miami, Miami is home to many entertainment venues, theaters, museums, parks and performing arts centers. The newest addition to the Miami arts scene is the Adrienne Arsht Center for the Performing Arts, the second-largest performing arts center in the United States after the Lincoln Center in New York City, and is the home of the Florida Grand Opera. Within it are the Ziff Ballet Opera House, the center's largest venue, the Knight Concert Hall, the Carnival Studio Theater and the Peacock Rehearsal Studio. The center attracts many large-scale operas, ballets, concerts, and musicals from around the world and is Florida's grandest performing arts center. Other performing arts venues in Miami include the Gusman Center for the Performing Arts, Coconut Grove Playhouse, Colony Theatre, Lincoln Theatre, New World Center, Actor's Playhouse at the Miracle Theatre, Jackie Gleason Theatre, Manuel Artime Theater, Ring Theatre, Playground Theatre, Wertheim Performing Arts Center, the Fair Expo Center and the Bayfront Park Amphitheater for outdoor music events.
What organization calls the Adrienne Arsht Center for the Performing Arts home?
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Answer: Florida Grand Opera

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A key aspect of the Gates Foundation's U.S. efforts involves an overhaul of the country's education policies at both the K-12 and college levels, including support for teacher evaluations and charter schools and opposition to seniority-based layoffs and other aspects of the education system that are typically backed by teachers' unions. It spent $373 million on education in 2009. It has also donated to the two largest national teachers' unions. The foundation was the biggest early backer of the Common Core State Standards Initiative.
What group has donated to the two largest national charter schools?
A: unanswerable

Context and question: A police force is a constituted body of persons empowered by the state to enforce the law, protect property, and limit civil disorder. Their powers include the legitimized use of force. The term is most commonly associated with police services of a sovereign state that are authorized to exercise the police power of that state within a defined legal or territorial area of responsibility. Police forces are often defined as being separate from military or other organizations involved in the defense of the state against foreign aggressors; however, gendarmerie are military units charged with civil policing.
What are gendarmerie?
Answer: military units charged with civil policing

Question: As for modern and contemporary architecture, Strasbourg possesses some fine Art Nouveau buildings (such as the huge Palais des Fetes and houses and villas like Villa Schutzenberger and Hotel Brion), good examples of post-World War II functional architecture (the Cite Rotterdam, for which Le Corbusier did not succeed in the architectural contest) and, in the very extended Quartier Europeen, some spectacular administrative buildings of sometimes utterly large size, among which the European Court of Human Rights building by Richard Rogers is arguably the finest. Other noticeable contemporary buildings are the new Music school Cite de la Musique et de la Danse, the Musee d'Art moderne et contemporain and the Hotel du Departement facing it, as well as, in the outskirts, the tramway-station Hoenheim-Nord designed by Zaha Hadid.
Is there an answer to this question: Who created the Cite de la Musique et de la Danse?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Drug discovery and development is very expensive; of all compounds investigated for use in humans only a small fraction are eventually approved in most nations by government appointed medical institutions or boards, who have to approve new drugs before they can be marketed in those countries. In 2010 18 NMEs (New Molecular Entities) were approved and three biologics by the FDA, or 21 in total, which is down from 26 in 2009 and 24 in 2008. On the other hand, there were only 18 approvals in total in 2007 and 22 back in 2006. Since 2001, the Center for Drug Evaluation and Research has averaged 22.9 approvals a year. This approval comes only after heavy investment in pre-clinical development and clinical trials, as well as a commitment to ongoing safety monitoring. Drugs which fail part-way through this process often incur large costs, while generating no revenue in return. If the cost of these failed drugs is taken into account, the cost of developing a successful new drug (new chemical entity, or NCE), has been estimated at about 1.3 billion USD(not including marketing expenses). Professors Light and Lexchin reported in 2012, however, that the rate of approval for new drugs has been a relatively stable average rate of 15 to 25 for decades.
How much does it cost to develop approvals?
A:
unanswerable