Problem: Buckingham Palace:

On 15 September 1940, known as the Battle of Britain Day, an RAF pilot, Ray Holmes of No. 504 Squadron RAF rammed a German bomber he believed was going to bomb the Palace. Holmes had run out of ammunition and made the quick decision to ram it. Holmes bailed out. Both aircraft crashed. In fact the Dornier Do 17 bomber was empty. It had already been damaged, two of its crew had been killed and the remainder bailed out. Its pilot, Feldwebel Robert Zehbe, landed, only to die later of wounds suffered during the attack. During the Dornier's descent, it somehow unloaded its bombs, one of which hit the Palace. It then crashed into the forecourt of London Victoria station. The bomber's engine was later exhibited at the Imperial War Museum in London. The British pilot became a King's Messenger after the war, and died at the age of 90 in 2005.

What type of aircraft was the German Plane?
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A: Dornier Do 17 bomber

Problem: Economy of Greece:

Between 2005 and 2011, Greece has had the highest percentage increase in industrial output compared to 2005 levels out of all European Union members, with an increase of 6%. Eurostat statistics show that the industrial sector was hit by the Greek financial crisis throughout 2009 and 2010, with domestic output decreasing by 5.8% and industrial production in general by 13.4%. Currently, Greece is ranked third in the European Union in the production of marble (over 920,000 tons), after Italy and Spain.

What is Greece ranked in the US in the production of marble?
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A: unanswerable

Problem: Carnival:

The Carnival of Malmedy is locally called Cwarme. Even if Malmedy is located in the east Belgium, near the German-speaking area, the Cwarme is a pure walloon and Latin carnival. The celebration takes place during 4 days before the Shrove Tuesday. The Cwarme Sunday is the most important and insteresting to see. All the old traditional costumes parade in the street. The Cwarme is a "street carnival" and is not only a parade. People who are disguised pass through the crowd and perform a part of the traditional costume they wear. The famous traditional costumes at the Cwarme of Malmedy are the Haguete, the Longues-Bresses and the Long-Ne.

How many days does Malmedy's festival take place before Shrove Tuesday?
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A: 4

Problem: Tibet:

This period also saw some contacts with Jesuits and Capuchins from Europe, and in 1774 a Scottish nobleman, George Bogle, came to Shigatse to investigate prospects of trade for the British East India Company. However, in the 19th century the situation of foreigners in Tibet grew more tenuous. The British Empire was encroaching from northern India into the Himalayas, the Emirate of Afghanistan and the Russian Empire were expanding into Central Asia and each power became suspicious of the others' intentions in Tibet.

When did the British and Russian empires begin encroaching on Tibet?
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A:
19th century