英语六级阅读理解模拟测试题 In a market system individual economic units are free to interact among each other in the marketplace
It is possible to buy commodities from other economic units or sell commodities to them
In a market, transactions may take place via barter or money exchange
In a barter economy, real goods such as automobiles, shoes, and pizzas are traded against each other
Obviously, finding somebody who wants to trade my old car in exchange for a sailboat may not always be an easy task
Hence, the introduction of money as a medium of exchange eases transactions considerably
In the modern market economy, goods and services are bought or sold for money
An alternative to the market system is administrative control by some agency over all transactions
This agency will issue edicts or c