1. Policies That Shift Supply and Demand Curves
1.1. Entry barrier
1.1.1. Goverment will raising the cost of entry cause supply curve to shift to the left
2. Policies That Create a Wedge Between Supply and Demand
2.1. Sales tax
2.1.1. it reducing supply causes the supply curve ti shift from right to left
2.2. Subsidy
2.2.1. it increasing the supply causes the supply curve to shift from left to right
2.3. Price floor
2.3.1. goverment sets price at minimum firm can legally charge which give firm benefit
2.4. Price ceiling
2.4.1. Goverment sets the price at the highest firm can legally charge and it brings benefit for consumer
3. Comparing Both Types of Policies : Imports
3.1. All free trade
3.1.1. Any firm can sell in this country without restriction
3.2. Ban all import
3.2.1. The goverment sets quota at zero on import
3.3. Set a tariff
3.3.1. The goverment imposes a tax on only imported goods
3.4. Set a positive quota
3.4.1. The goverment limits import
4. Zero Profit For Competitive Firms in The Long Run
4.1. Zero long-run profit with free entry
4.1.1. if the firm earns zero economic profit, it can stay in business
4.1.2. if the firm earns zero business profit, it have to shut down
4.2. Zero long-run profit when entry is limited
4.2.1. in some market, the limited number of firms is that the supply of an input id limited
5. Consumer Welfare
5.1. Measuring consumer welfare using a demand curve
5.1.1. Demand curve : consumer's marginal willingness to pay the maximum amount of money, consumer will spend for an extra unit of good
5.1.2. Consumer surply : The maximum amount of money comsumer is willing to pay minus actual amount of payment
5.2. the benefits the consumer gets from consuming that good minus what the consumer paid to buy the good
5.2.1. actual revenue minus the minimum revenue the producer has to receive