Помогите пожалуйста, решить упражнение.
Refer the following statements to the past;
M o d e l : Economic incentives influence our decision about what and where to buy.
Economic incentives influenced our decision about what and where to buy.
1. What you see at the auction is the rationing effect of prices.
2. Prices encourage producers to increase their level of output.
3. The law of demand describes the relationship between prices and the quantity of goods and services.
4. They sell these goods because they want to have a profit from such transaction.
5. Adam Smith describes the principal elements of the economic system in his book «The Wealth ofNations».