Which of the following elements is a representative element? a. chromium (cr) b. aluminum (al) c. mercury (hg) d. silver (ag)

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.

Why do oxygen have a strong attractive force for electrons

Which would freeze at a higher temperature: the great salt lake or lake tahoe? a. lake tahoe would freeze at a higher temperature. b. the great salt lake would freeze at a higher temperature. c. both lakes would freeze at the same temperature.