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Around the world the most significant restriction on access to potable water is money. While access to raw water sources, clean or otherwise, is important, the purification process itself is expensive. Once water has been rendered potable, it is important that it be delivered without reintroducing contamination.
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A rainforest is an area of tall, mostly evergreen trees and a high amount of rainfall. Rainforests are Earth's oldest living ecosystems, with some surviving in their present form for at least 70 million years.
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All igneous rocks the basis of the rock cycle are formed by plate tectonics. ... The heat from the mantle that fuels plate tectonics causes both igneous and sedimentary rocks to be turned into metamorphic rocks. The metamorphic rocks can be eroded into sedimentary rocks are remelted back into igneous.
