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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.
Who engineered the Dujiangyan irrigation system to control the Min River?
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The answer: Li Bing


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The sensitivity of Earth-based infrared telescopes is significantly limited by water vapor in the atmosphere, which absorbs a portion of the infrared radiation arriving from space outside of selected atmospheric windows. This limitation can be partially alleviated by placing the telescope observatory at a high altitude, or by carrying the telescope aloft with a balloon or an aircraft. Space telescopes do not suffer from this handicap, and so outer space is considered the ideal location for infrared astronomy.
What limits the sensitivity of infrared telescopes on Earth?
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The answer: water vapor in the atmosphere


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Drying involves using air and/or heat to remove water from the paper sheets; in the earliest days of paper making this was done by hanging the sheets like laundry; in more modern times various forms of heated drying mechanisms are used. On the paper machine the most common is the steam heated can dryer. These can reach temperatures above 200 °F (93 °C) and are used in long sequences of more than 40 cans; where the heat produced by these can easily dry the paper to less than 6% moisture.
What is the main component of drying the paper?
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The answer: air


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In the 1990s Rhino Records issued a series of boxed sets of 78 rpm reissues of early rock and roll hits, intended for owners of vintage jukeboxes. This was a disaster because Rhino did not warn customers that their records were made of vinyl, and that the vintage 78 RPM juke boxes were designed with heavy tone arms and steel needles to play the hard shellac records of their time. This failure to warn customers gave the Rhino 78 records a bad reputation,[citation needed] as they were destroyed by old juke boxes and old record players but played very well on newer 78-capable turntables with modern lightweight tone arms and jewel needles.
For whom was the 1990 release of 78 rpm intended?
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The answer:
owners of vintage jukeboxes