Trade involves the transfer of goods or services from one person or entity to another, often in exchange for money. A system or network that allows trade is called a market.
The product of mental labor — science — always stands far below its value, because the labor-time necessary to reproduce it has no relation at all to the labor-time required for its original production.
Karl Marx Addenda, "Relative and Absolute Surplus Value" in Economic Manuscripts (1861–63).
Rivers, lakes and coastal areas are under pressure from human activities that result in pollution, intensive land use and the degradation of natural habitats. To better manage challenges in this area, an EU-funded project developed methods for assessing and restoring aquatic ecosystems.
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