Here is a question about this article: The mantle is equivalent to 10 to 15 Earth masses and is rich in water, ammonia and methane. As is customary in planetary science, this mixture is referred to as icy even though it is a hot, dense fluid. This fluid, which has a high electrical conductivity, is sometimes called a waterammonia ocean. The mantle may consist of a layer of ionic water in which the water molecules break down into a soup of hydrogen and oxygen ions, and deeper down superionic water in which the oxygen crystallises but the hydrogen ions float around freely within the oxygen lattice. At a depth of 7000 km, the conditions may be such that methane decomposes into diamond crystals that rain downwards like hailstones. Very-high-pressure experiments at the Lawrence Livermore National Laboratory suggest that the base of the mantle may comprise an ocean of liquid carbon with floating solid 'diamonds'.
What is the answer to this question: How deep does Neptune's water-ammonia ocean go?
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So... 7000 km

Here is a question about this article: The Henry Art Gallery opened in 1927, the first public art museum in Washington. The Seattle Art Museum (SAM) opened in 1933; SAM opened a museum downtown in 1991 (expanded and reopened 2007); since 1991, the 1933 building has been SAM's Seattle Asian Art Museum (SAAM). SAM also operates the Olympic Sculpture Park (opened 2007) on the waterfront north of the downtown piers. The Frye Art Museum is a free museum on First Hill. Regional history collections are at the Loghouse Museum in Alki, Klondike Gold Rush National Historical Park, the Museum of History and Industry and the Burke Museum of Natural History and Culture. Industry collections are at the Center for Wooden Boats and the adjacent Northwest Seaport, the Seattle Metropolitan Police Museum, and the Museum of Flight. Regional ethnic collections include the Nordic Heritage Museum, the Wing Luke Asian Museum and the Northwest African American Museum. Seattle has artist-run galleries, including 10-year veteran Soil Art Gallery, and the newer Crawl Space Gallery.
What is the answer to this question: When did the first art gallery open in Washington state?
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So... 1927

Here is a question about this article: The causes of the Franco-Prussian War are deeply rooted in the events surrounding the unification of Germany. In the aftermath of the AustroPrussian War of 1866, Prussia had annexed numerous territories and formed the North German Confederation. This new power destabilized the European balance of power established by the Congress of Vienna in 1815 after the Napoleonic Wars. Napoleon III, then the emperor of France, demanded compensations in Belgium and on the left bank of the Rhine to secure France's strategic position, which the Prussian chancellor, Otto von Bismarck, flatly refused. Prussia then turned its attention towards the south of Germany, where it sought to incorporate the southern German kingdoms, Bavaria, Wurttemberg, Baden and Hesse-Darmstadt, into a unified Prussia-dominated Germany. France was strongly opposed to any further alliance of German states, which would have significantly strengthened the Prussian military.
What is the answer to this question: In the aftermath of the Austro-Prussian war, formed what group?
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So...
North German Confederation