ED, supply& demand elasticity questions. 10 marks!!

Supply and demand
http://en.wikipedia.org/wiki/Supply_and_demand

In economics, supply and demand describe market relations between prospective sellers and buyers of a good. The supply and demand model determines price and quantity sold in the market. The model is fundamental in microeconomic analysis of buyers and sellers and of their interactions in a market. It is also used as a point of departure for other economic models and theories. The model predicts that in a competitive market, price will function to equalize the quantity demanded by consumers and the quantity supplied by producers, resulting in an economic equilibrium of price and quantity. The model incorporates other factors changing such equilibrium as reflected in a shift of demand or supply.

如果你想睇下d 圖點書, 你就去下面的網頁度參考啦~
Price elasticity of demand
http://en.wikipedia.org/wiki/Price_elasticity_of_demand

Price elasticity of supply
http://en.wikipedia.org/wiki/Price_elasticity_of_supply

希望幫到你啦~ ^o^

會
條demand curve 要畫得斜 (即係接近直線)