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
Nearly zero-energy buildings are a major element of European climate policy, and by 2021 every new building has to meet this standard. Hybrid systems that are 100 % renewables will help transform the heating and cooling market, providing improved efficiency and carbon dioxide reductions.
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