Why are the free water molecules diffusing out of the vessel?

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

i need an image of the diagram

the water is warmed up by the sun and then it evaporates into the atmosphere. the sunlight warms the water by its heat. water is then cooled down and condensation takes place. the water then finally returns back to the earth by the process of precipitation in the form of rain or ice.

explanation:

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