"Which inference can be made from the graphs?
(1)The increase in sewage waste from 1950 to 1970 was due to a decreasing human population.
(2)The decrease in sewage waste shows that the environmental problems associated with land pollution have been solved.
(3)Sewage waste is a good source of nutrients for most fish.
(4)Increases in sewage waste were responsible for decreasing oxygen levels in the lake."
(1)The increase in sewage waste from 1950 to 1970 was due to a decreasing human population.
(2)The decrease in sewage waste shows that the environmental problems associated with land pollution have been solved.
(3)Sewage waste is a good source of nutrients for most fish.
(4)Increases in sewage waste were responsible for decreasing oxygen levels in the lake."