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In 1845, the Neapolitan architect Gaetano Genovese installed in the Royal Palace of Caserta the "Flying Chair", an elevator ahead of its time, covered with chestnut wood outside and with maple wood inside. It included a light, two benches and a hand operated signal, and could be activated from the outside, without any effort on the part of the occupants. Traction was controlled by a motor mechanic utilizing a system of toothed wheels. A safety system was designed to take effect if the cords broke. It consisted of a beam pushed outwards by a steel spring.
What did the safety system consist of?
A: a beam pushed outwards by a steel spring

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These developments led to the theory of conservation of energy, formalized largely by William Thomson (Lord Kelvin) as the field of thermodynamics. Thermodynamics aided the rapid development of explanations of chemical processes by Rudolf Clausius, Josiah Willard Gibbs, and Walther Nernst. It also led to a mathematical formulation of the concept of entropy by Clausius and to the introduction of laws of radiant energy by Jozef Stefan. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time. Thus, since 1918, theorists have understood that the law of conservation of energy is the direct mathematical consequence of the translational symmetry of the quantity conjugate to energy, namely time.
Who largely formalized the developments that led to the theory of conservation of energy?
A: William Thomson

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A referee may stop the match when they or official ring physician decides that a wrestler cannot safely continue the match. This may be decided if the wrestler cannot continue the match due to an injury. At the Great American Bash in 2008, Chris Jericho was declared the winner of a match against Shawn Michaels when Michaels could not defend himself due to excessive blood loss and impaired vision. At NXT TakeOver: Rival in 2015, the referee stopped the match when Sami Zayn could not defend himself due to an injury sustained against Kevin Owens for the NXT Championship.
Why couldn't Shawn Michaels defend himself?
A: due to excessive blood loss and impaired vision

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The region, as part of Lorraine, was part of the Holy Roman Empire, and then was gradually annexed by France in the 17th century, and formalized as one of the provinces of France. The Calvinist manufacturing republic of Mulhouse, known as Stadtrepublik Mulhausen, became a part of Alsace after a vote by its citizens on 4 January 1798. Alsace is frequently mentioned with and as part of Lorraine and the former duchy of Lorraine, since it was a vital part of the duchy, and later because German possession as the imperial province (Alsace-Lorraine, 18711918) was contested in the 19th and 20th centuries; France and Germany exchanged control of parts of Lorraine (including Alsace) four times in 75 years.
When did the Holy Roman Empire begin?
A:
unanswerable