Problem: Saint Barth%C3%A9lemy:

Among the notable structures in the town are the three forts built by the Swedes for defense purposes. One of these forts, known as Fort Oscar (formerly Gustav Adolph), which overlooks the sea is located on the far side of La Pointe. However, the ruins have been replaced by a modern military building which now houses the local gendarmerie. The other fort known as Fort Karl now presents a very few ruins. The third fort built by the Swedes is the Fort Gustav, which is also seen in ruins strewn around the weather station and the Light House. The fort built in 1787 over a hill slope has ruins of ramparts, guardhouse, munitions depot, wood-burning oven and so forth.

What was the former name of Fort Oscar?
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A: Gustav Adolph

Problem: Eton College:

As with other public schools, a scheme was devised towards the end of the 19th century to familiarize privileged schoolboys with social conditions in deprived areas. The project of establishing an 'Eton Mission' in the crowded district of Hackney Wick in east London was started at the beginning of 1880, and lasted until 1971 when it was decided that a more local project (at Dorney) would be more realistic. However over the years much money was raised for the Eton Mission, a fine church by G. F. Bodley was erected, many Etonians visited, and stimulated among other things the Eton Manor Boys' Club, a notable rowing club which has survived the Mission itself, and the 59 Club for motorcyclists.

Why did construction of Eton Mission cease in 1971?
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A: it was decided that a more local project (at Dorney) would be more realistic

Problem: Charleston, South Carolina:

Public institutions of higher education in Charleston include the College of Charleston (the nation's 13th-oldest university), The Citadel, The Military College of South Carolina, and the Medical University of South Carolina. The city is also home to private universities, including the Charleston School of Law . Charleston is also home to the Roper Hospital School of Practical Nursing, and the city has a downtown satellite campus for the region's technical school, Trident Technical College. Charleston is also the location for the only college in the country that offers bachelor's degrees in the building arts, The American College of the Building Arts. The Art Institute of Charleston, located downtown on North Market Street, opened in 2007.

What Charleston College offers no degree in Building Arts?
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A: unanswerable

Problem: Railway electrification system:

In comparison to the principal alternative, the diesel engine, electric railways offer substantially better energy efficiency, lower emissions and lower operating costs. Electric locomotives are usually quieter, more powerful, and more responsive and reliable than diesels. They have no local emissions, an important advantage in tunnels and urban areas. Some electric traction systems provide regenerative braking that turns the train's kinetic energy back into electricity and returns it to the supply system to be used by other trains or the general utility grid. While diesel locomotives burn petroleum, electricity is generated from diverse sources including many that do not produce carbon dioxide such as nuclear power and renewable forms including hydroelectric, geothermal, wind and solar.

What does not offer better emissions efficiency?
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A:
unanswerable