Macro, please help?

Can someone help me answer these questions please....

1. How do economists measure the value of anything?
2. What determines the price and quantity of any good or service? graph
3. What is opportunity cost and why is there no free lunch?
4. What does the invisible hand mean, and why does it suggest laisser-faire?
5. What are the three questions answered by any economic system and how are they answered under a market-based system
6. What is the difference between capitalism, socialism, communism
7. What is the definition of Microeconomics? Macroeconomics? Economics?

short answer is ok .. just explain ...

1. They conduct research and analyze graphs
2. The supply and demand for a product in a given market
3. it is the cost of the next best alternative.
4. The invisible hand was coined by Adam Smith in his book THE WEALTH OF NATIONS. It means that markets tend to stabalize where supply equals demand and they do so without any apparent regulation or control. This suggests laissez fair because it argues for uniteruption of markets (private is better than public).
5. ? sorry, i don't have a text book in fron of me
6. Capitalism stresses the free market ideas and has limited government intervention. Socialism stesses government control of production and consumer consumption- every person, theoretically, it taken care of by the government. (But we knoe this is never the case) Communism is a branch of socialism that stresses the public ownership of everything. In other words you do not own your house, the government owns your house and can take it from you at any time for 'the good of the people".
7. Microeconomics is the study of economic behavior on a small scale. This incorperate individuals, communities, cities, and small markets. Macroeconomics is the study of economic behavior on a large scale. Traditionally this include individual contries and the world.

Economics the the study of how individuals make decisions based on insentives and disinsentives.

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