Elements in this family have 1 valence electron?

The variability in marine salinity between habitats does not impact the fish living there. select the best answer from the choices provided t f

How do you know when a chemical reaction has occurred

15. which of the following is not human-caused groundwater pollution? a. water in an aquifer dissolves elements such as arsenic and mercury from surrounding rock. b. water in an aquifer is contaminated by leachate that seeps into the ground from a landfill. c. water in an aquifer becomes polluted with chemicals used in hydraulic fracturing, or fracking. d. water in an aquifer absorbs harmful bacteria from the drainage field of a septic tank.