How to tell if a solution is unsaturated saturated or supersaturated?

Read these sentences from the text. near the equator, the tropics receive the most rain on a consistent basis. as a result, the fresh water falling into the ocean decrease the salinity of the surface water in that region. [. .] . . as the salt content of sea water increases, so does its density. what can you infer about how rain affects the density of surface water near the equator?

List four observations that indicate that a chemical reaction may be taking place

Chemistry worksheet - i am not sure what they are asking for exactly?