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The Galactic Center (or Galactic Centre) is the rotational center of the Milky Way galaxy; it is a supermassive black hole of 4.100 ± 0.034 million solar masses, which powers the compact radio source Sagittarius A*.
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Theoretically speaking, for a scientist to determain weather an unknown substance is set out to be an element, compound, solution, or heterogenous mixture is they would have to look at the substances properties, and appearance, using this will allow the scientist to outlook what it shall be.
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Water clarity is a measure of how far down light can penetrate through the water column. ... For example, clearer water allows more sunlight to reach submerged aquatic vegetation. The vegetation, in turn, produces oxygen, provides habitat for fish and shellfish and provides food for waterfowl, fish and mammals.
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