Color and luster are two ways to identify an unknown metal. Other ways include weight and composition.
<span>Steno’s final principle is the “principle of lateral continuity,” which says that sediment layers spread out until they reach an obstacle that keeps them from spreading further, the way soup spreads out in a bowl until it reaches the sides of the dish. “Wherever bared edges of strata are seen,” he wrote, “either a continuation of that same strata must be looked for or another solid substance must be found that kept the material of the strata from being dispersed.”
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It would sometimes signify the unity of two separate kingdoms
Answer: "the Earth's mantle" .
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The asthenosphere "floats" on the "mantle" [of the interior] Earth.
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1.push factor
2.industrialization
3.utban crowding
4.income gap
5.pull factors
