The world's economies interact with each other by trading. For example, if oil is easier to access in Saudi Arabia than America, it will be less expensive, so we trade. The economies affect one another by giving each other easier access to different resources and products.
By composition, group, and method of lithification. Composition is what its made of, group is whether the rock has grain of layers, and method of lithification is whether is was formed from compaction, cementation, etc<span />
<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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<span>the magnetic compass and gunpowder</span>
