Mathematics (from Greek μάθημα máthēma, "knowledge, study, learning") is the study of such topics as quantity, structure, space, and change. It has no generally accepted definition.
Mathematics is a versatile art; it can be applied to widely different purposes. Math has no morality; it does not care what it counts or what it proves.
Brian Stableford, Ashes and Tombstones, in Peter Crowther (ed.) Moon Shots (1999), reprinted in David G. Hartwell (ed.) Year's Best SF 5 (2000), p. 412
Shallow lakes have been greatly affected by increased concentrations of nitrogen and phosphorus from intensive agriculture and increased human populations. These key nutrients for plant growth enter the aquatic environment, changing clear water to turbid through a phenomenon called eutrophication.
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