Problem: Estonia:

After centuries of Danish, Swedish and German rule the native Estonians started to yearn for independence during the period of national awakening while being governed by the Russian Empire. Established on 24 February 1918, the Republic of Estonia came into existence towards the end of World War I. During World War II, Estonia was then occupied by the Soviet Union in 1940, then Nazi Germany a year later and again in 1944 establishing the Estonian Soviet Socialist Republic. In 1988, during the Singing Revolution, the Estonian SSR issued the Estonian Sovereignty Declaration to defy against the illegal Soviet rule. Estonia then restored its independence during the 1991 coup by the Soviets on the night of 20 August 1991.

What year was the Republic of Estonia established?
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A: 1918

Problem: New York City:

Major tourist destinations include Times Square; Broadway theater productions; the Empire State Building; the Statue of Liberty; Ellis Island; the United Nations Headquarters; museums such as the Metropolitan Museum of Art; greenspaces such as Central Park and Washington Square Park; Rockefeller Center; the Manhattan Chinatown; luxury shopping along Fifth and Madison Avenues; and events such as the Halloween Parade in Greenwich Village; the Macy's Thanksgiving Day Parade; the lighting of the Rockefeller Center Christmas Tree; the St. Patrick's Day parade; seasonal activities such as ice skating in Central Park in the wintertime; the Tribeca Film Festival; and free performances in Central Park at Summerstage. Major attractions in the boroughs outside Manhattan include Flushing Meadows-Corona Park and the Unisphere in Queens; the Bronx Zoo; Coney Island, Brooklyn; and the New York Botanical Garden in the Bronx. The New York Wheel, a 630-foot ferris wheel, was under construction at the northern shore of Staten Island in 2015, overlooking the Statue of Liberty, New York Harbor, and the Lower Manhattan skyline.

In what borough is the Unisphere located?
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A: Queens

Problem: Canadian football:

There are many rules to contact in this type of football. First, the only player on the field who may be legally tackled is the player currently in possession of the football (the ball carrier). Second, a receiver, that is to say, an offensive player sent down the field to receive a pass, may not be interfered with (have his motion impeded, be blocked, etc.) unless he is within one yard of the line of scrimmage (instead of 5 yards (4.6 m) in American football). Any player may block another player's passage, so long as he does not hold or trip the player he intends to block. The kicker may not be contacted after the kick but before his kicking leg returns to the ground (this rule is not enforced upon a player who has blocked a kick), and the quarterback, having already thrown the ball, may not be hit or tackled.

What player can't be interfered with unless he is within one yard of any player?
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A: unanswerable

Problem: Han dynasty:

From roughly 115 to 60 BC, Han forces fought the Xiongnu over control of the oasis city-states in the Tarim Basin. Han was eventually victorious and established the Protectorate of the Western Regions in 60 BC, which dealt with the region's defense and foreign affairs. The Han also expanded southward. The naval conquest of Nanyue in 111 BC expanded the Han realm into what are now modern Guangdong, Guangxi, and northern Vietnam. Yunnan was brought into the Han realm with the conquest of the Dian Kingdom in 109 BC, followed by parts of the Korean Peninsula with the colonial establishments of Xuantu Commandery and Lelang Commandery in 108 BC. In China's first known nationwide census taken in 2 AD, the population was registered as having 57,671,400 individuals in 12,366,470 households.

When was the first national census taken in China?
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A:
2 AD