Problem: Qin armies finished their conquest of the kingdoms of Shu and Ba by 316 BC. Any written records and civil achievements of earlier kingdoms were destroyed. Qin administrators introduced improved agricultural technology. Li Bing, engineered the Dujiangyan irrigation system to control the Min River, a major tributary of the Yangtze. This innovative hydraulic system was composed of movable weirs which could be adjusted for high or low water flow according to the season, to either provide irrigation or prevent floods. The increased agricultural output and taxes made the area a source of provisions and men for Qin's unification of China.
The Dujiangyan irrigation system was used for what purpose?
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Answer: to either provide irrigation or prevent floods.

Problem: War work again brought local prosperity during World War II, this time centered on Boeing aircraft. The war dispersed the city's numerous Japanese-American businessmen due to the Japanese American internment. After the war, the local economy dipped. It rose again with Boeing's growing dominance in the commercial airliner market. Seattle celebrated its restored prosperity and made a bid for world recognition with the Century 21 Exposition, the 1962 World's Fair. Another major local economic downturn was in the late 1960s and early 1970s, at a time when Boeing was heavily affected by the oil crises, loss of Government contracts, and costs and delays associated with the Boeing 747. Many people left the area to look for work elsewhere, and two local real estate agents put up a billboard reading "Will the last person leaving Seattle Turn out the lights."
How did Seattle celebrate its economic rise in 1962?
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Answer: 1962 World's Fair

Problem: The console was first officially announced at E3 2005, and was released at the end of 2006. It was the first console to use Blu-ray Disc as its primary storage medium. The console was the first PlayStation to integrate social gaming services, included it being the first to introduce Sony's social gaming service, PlayStation Network, and its remote connectivity with PlayStation Portable and PlayStation Vita, being able to remote control the console from the devices. In September 2009, the Slim model of the PlayStation 3 was released, being lighter and thinner than the original version, which notably featured a redesigned logo and marketing design, as well as a minor start-up change in software. A Super Slim variation was then released in late 2012, further refining and redesigning the console. As of March 2016, PlayStation 3 has sold 85 million units worldwide. Its successor, the PlayStation 4, was released later in November 2013.
What year did the Super Slim model hit stores?
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Answer:
2012