river bed (river beds plural) , riverbed A river bed is the ground which a river flows over. n-count. up-river, upriver. Something that is moving up-river is moving towards the source of a river, from a point down the river.
In economics, the term trade-off is often expressed as an opportunity cost, which is the most preferred possible alternative. A trade-off involves a sacrifice that must be made to get a certain product or experience. A person gives up the opportunity to buy 'good B,' because they want to buy 'good A' instead.
International trade. International trade is defined as trade between two or more partners from different countries (an exporter and an importer). Early international trade consisted mostly of barter transactions. International trade is also a branch of economics. Traditionally, international trade is justified in economics by comparative advantage theory. New developments include in patterns of international trade: the integration of countries into trade blocks (eg.