4. Acid rain is formed due to the contribution from the following pair of gases: 1) Methane and ozone
2) Oxygen and nitrous oxide
3) Methane and sulphur dioxide
4) Carbon dioxide and sulphur dioxide

Which of the following statements about pesticides and residue is false? a. most conventionally grown produce has detectable levels of pesticides when purchased from the store.b. the us government has determined that small levels of pesticides in produce is safe for humanconsumption.c. organic produce always will be pesticide-free.d. farm workers, children, and pregnant women are at greatest health risk from pesticides. select the best answer from the choices provided.

Which evidence is most likely used to indicate the beginning of solar system formation? a. materials combined to form a mass. b. materials were pulled together by gravity. c. water condensed and collected to form oceans. d. different species of microorganisms lived on earth.

Which statements about wells are true? check all that apply. a) wells bring groundwater from the unsaturated zone to the surface of the water. b) wells need to be drilled below the water table. c) if water is pumped from a well too quicky, the well may run dry. d) water from wells is generally not safe to drink. e) water gushes from artesian wells due to pressure.