Problem: Asphalt:

Because of the difficulty of moving crude bitumen through pipelines, non-upgraded bitumen is usually diluted with natural-gas condensate in a form called dilbit or with synthetic crude oil, called synbit. However, to meet international competition, much non-upgraded bitumen is now sold as a blend of multiple grades of bitumen, conventional crude oil, synthetic crude oil, and condensate in a standardized benchmark product such as Western Canadian Select. This sour, heavy crude oil blend is designed to have uniform refining characteristics to compete with internationally marketed heavy oils such as Mexican Mayan or Arabian Dubai Crude.

What is the natural gas condensate used to dilute bitumen?
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A: dilbit

Problem: Videoconferencing:

While videoconferencing technology was initially used primarily within internal corporate communication networks, one of the first community service usages of the technology started in 1992 through a unique partnership with PictureTel and IBM Corporations which at the time were promoting a jointly developed desktop based videoconferencing product known as the PCS/1. Over the next 15 years, Project DIANE (Diversified Information and Assistance Network) grew to utilize a variety of videoconferencing platforms to create a multi-state cooperative public service and distance education network consisting of several hundred schools, neighborhood centers, libraries, science museums, zoos and parks, public assistance centers, and other community oriented organizations.

What did IBM Corporations grow to create over the next 15 years?
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A: unanswerable

Problem: Alaska:

The bulk of remaining commercial flight offerings come from small regional commuter airlines such as Ravn Alaska, PenAir, and Frontier Flying Service. The smallest towns and villages must rely on scheduled or chartered bush flying services using general aviation aircraft such as the Cessna Caravan, the most popular aircraft in use in the state. Much of this service can be attributed to the Alaska bypass mail program which subsidizes bulk mail delivery to Alaskan rural communities. The program requires 70% of that subsidy to go to carriers who offer passenger service to the communities.

What are the names of all regional Alaskan airlines?
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A: unanswerable

Problem: London:

London's buildings are too diverse to be characterised by any particular architectural style, partly because of their varying ages. Many grand houses and public buildings, such as the National Gallery, are constructed from Portland stone. Some areas of the city, particularly those just west of the centre, are characterised by white stucco or whitewashed buildings. Few structures in central London pre-date the Great Fire of 1666, these being a few trace Roman remains, the Tower of London and a few scattered Tudor survivors in the City. Further out is, for example, the Tudor period Hampton Court Palace, England's oldest surviving Tudor palace, built by Cardinal Thomas Wolsey c.1515.

What is England's oldest standing palace from the Tudor period?
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A:
Hampton Court Palace