要做一个关于price的英语演讲，谁能发点英语范文或者是相关的英语资料

Price in economics and business is the result of an exchange and from that trade we assign a numerical monetary value to a good, service or asset. If I trade 4 apples for an orange, the price of an orange is 4 - apples. Inversely, the price of an apple is 1/4 oranges.

Price is only part of the information we get from observing an exchange. The other part is the volume of the goods traded per unit time, called the rate of purchase or sale. From this additional information we understand the extent of the market and the elasticity of the demand and supply.

The concept of price is central to microeconomics where it is one of the most important variables in resource allocation theory (also called price theory). Price is also central to marketing where it is one of the four variables in the marketing mix that business people use to develop a marketing plan.

In general terms price is the result of an exchange or transaction that takes place between two p