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97.5% of the water in the world is in the oceans and inland seas as salt water and 2.5% as fresh water. However, 87% of this fresh water is found in glaciers, soil, atmosphere, groundwater and is...

2019 will be the 150th anniversary since Dmitry Mendeleev discovered the Periodic System and has been proclaimed the “International Year of the Periodic Table of Chemical Elements” (IYPT2019).Prepare...

Space Pollution : In the most general sense, the term space pollution includes both the natural micrometeoroid and man-made orbital debris components of the space environment; however, as "pollution"...