Which half- reaction equation represents reduction?
1) Cu --> Cu^2+ + 2e^-
2) Cu^2+ + 2e^- --> Cu
3) Ag + e^- --> Ag^+
4) Ag^+ --> Ag + e^-

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.