Demand and supply

圖片參考：http://imgcld.yimg.com/8/n/HA00154148/o/701101280127113873375060.jpg



A講緊price change along a demand curve.
B講緊change in demand

2011-01-30 21:30:24 補充：
好。
首先A係講緊需求定律,即係price升,quatity跌。
但係B講緊需求變化(change in demand),好似幅圖咁,雖然price 係升左,但quatity都升

This question must be talking about elasticity...

A is elastic demand...

B is inelastic demand.....

Am i right??

2011-01-29 21:32:39 補充：
This question is related to elasticity of demand with the change in price.

A- Demand is elastic for chocolate
B- Demand is inelastic for chocolate

Elastic- small change in price caused a large change in quantity demanded
Inelastic- small change in price caused a large change in quantity demanded.

The diagram below is elastic:

圖片參考：http://imgcld.yimg.com/8/n/HA06682457/o/701101280127113873375060.jpg