Life.
Water
Water :)
Water
Water.
The three conditions needed for life as we know it are: liquid water, a source of energy, and a stable environment with suitable temperatures.
caretakers and water
on body
on body
Since life as we know it requires water, scienctists hypothesize that Mars may have once had the conditions needed for life to exist.
Water is necessary for practically all activity needed to support life. All chemical reactions require water.
Water, Air, Food , and Sunlight.