Quick, which physical evidence supports the theory that all continents were once together and have separated over time? common marine animal fossils found in various continents matching coastlines of africa and south america that most earthquakes occur along a plate boundary oceanic ridge near a divergent plate boundary

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.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.