Answer:
The answer would be Diffusion because it does not require the use of energy
Surface runoff is a term used to describe when soil is infiltrated to full capacity and excess water, from rain, snowmelt, or other sources flow over the land. This is a major component of the water cycle or the hydrological cycle.
When the temperature of the air becomes almost equal to the dew point the air becomes saturated and the relative humidity during this condition becomes 100%. If the temperature of the air decrease below the dew point the relative humidity will be 100% or exceeds 100%. This condition, when the temperature of the air decreases below the dew point is called supersaturation but most of the time the temperature of the air will be lower than the dew point.
Valves ensure blood flows toward your heart. Vein valves work to bring the blood that flowed down via arteries back up to your heart.