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   available      critical      expensive      frozen      one      plants      polar      precious      salt      three   
Water is probably Earth's most resource. After all, we can't live without it. Approximately ninety-seven percent of Earth's water is water. The process of desalination, or removing salt from water, is . This leaves only about percent that is freshwater for meeting the needs of people, and animals. This is why there is such concern for protection this rare and resource. Unfortunately, only about a third of our freshwater is even for us to use. The rest is solid in glaciers, in the snow on high mountaintops and in the ice caps. So the end result is that we have only about percent of all the water on Earth that we can use.