During the water cycle some of the water in the oceans and freshwater bodies, such as lakes and rivers, is warmed by the sun and evaporates. During the process of evaporation, impurities in the water are left behind. As a result, the water that goes into the atmosphere is cleaner than it was on Earth.
They can be single or multicellular and they are bigger than prokaryotes. They have a distinct nucleus and membrane-bound organelles, so that option would be incorrect. I hope this helped.
