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).
Photovoltaic (PV) systems that harness the Sun's virtually limitless supply of energy are now visible in limited locations across Europe. A new open-source simulation platform will foster lower costs and enhanced performance for mass market uptake.
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