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In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg's uncertainty principle formulated in 1927, predict a fundamental limit within which instantaneous position and momentum, or energy and time can be measured. This has far reaching consequences on the "emptiness" of space between particles. In the late 20th century, so-called virtual particles that arise spontaneously from empty space were confirmed.
What year was the uncertainty principle formed?
A: 1927,

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Apple has generally dominated the premium PC market, having a 91 percent market share for PCs priced at more than $1,000 in 2009, according to NPD. The Macintosh took 45 percent of operating profits in the PC industry during Q4 2012, compared to 13 percent for Dell, seven percent for Hewlett Packard, six percent for Lenovo and Asus, and one percent for Acer. While sales of the Macintosh have largely held steady, in comparison to Apple's sales of the iPhone and iPad which increased significantly during the 2010s, Macintosh computers still enjoy high margins on a per unit basis, with the majority being their MacBooks that are focused on the ultraportable niche that is the most profitable and only growing segment of PCs. It also helped that the Macintosh lineup is simple, updated on a yearly schedule, and consistent across both Apple retail stores, and authorized resellers where they have a special "store within a store" section to distinguish them from Windows PCs. In contrast, Windows PC manufacturers generally have a wide range of offerings, selling only a portion through retail with a full selection on the web, and often with limited-time or region-specific models. The Macintosh ranked third on the "list of intended brands for desktop purchases" for the 2011 holiday season, then moved up to second in 2012 by displacing Hewlett Packard, and in 2013 took the top spot ahead of Dell.
Who did Macintosh displace from 2nd place on the 2011 holiday season "list of intended brands for desktop purchases"?
A: unanswerable

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Strasbourg features a number of prominent parks, of which several are of cultural and historical interest: the Parc de l'Orangerie, laid out as a French garden by Andre le Notre and remodeled as an English garden on behalf of Josephine de Beauharnais, now displaying noteworthy French gardens, a neo-classical castle and a small zoo; the Parc de la Citadelle, built around impressive remains of the 17th-century fortress erected close to the Rhine by Vauban; the Parc de Pourtales, laid out in English style around a baroque castle (heavily restored in the 19th century) that now houses a small three-star hotel, and featuring an open-air museum of international contemporary sculpture. The Jardin botanique de l'Universite de Strasbourg (botanical garden) was created under the German administration next to the Observatory of Strasbourg, built in 1881, and still owns some greenhouses of those times. The Parc des Contades, although the oldest park of the city, was completely remodeled after World War II. The futuristic Parc des Poteries is an example of European park-conception in the late 1990s. The Jardin des deux Rives, spread over Strasbourg and Kehl on both sides of the Rhine opened in 2004 and is the most extended (60-hectare) park of the agglomeration. The most recent park is Parc du Heyritz (8,7 ha), opened in 2014 along a canal facing the hopital civil.
Who designed the Parc de l'Orangerie?
A: Andre le Notre

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A literary technique or literary device can be used by authors in order to enhance the written framework of a piece of literature, and produce specific effects. Literary techniques encompass a wide range of approaches to crafting a work: whether a work is narrated in first-person or from another perspective, whether to use a traditional linear narrative or a nonlinear narrative, or the choice of literary genre, are all examples of literary technique. They may indicate to a reader that there is a familiar structure and presentation to a work, such as a conventional murder-mystery novel; or, the author may choose to experiment with their technique to surprise the reader.
In what type of writing would a more familiar, standard literary narrative structure be employed?
A:
a conventional murder-mystery novel