As water moves from sink to sink, what happens to the TOTAL amount of water on Earth?

It stays the same

Explanation:

When water moves from sink to sink it is simply put back in to the water cycle and although the water goes down the sink it isn't gone for ever it goes back to the pipes and then to the water purification plant and the then to another sink some where else.

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.