Constructed Response (3 paragraphs) 30 pts Water is a very common substance on Earth, covering over two-thirds of its surface. But less than one percent of the water on Earth is fresh water that can be used by humans. As human populations grow, the stress on water resources will continue to increase.

Describe how we as a global community might come together to save more water or use water that needs to be processed to consume (ocean water for example)

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.