Please give me short explanation:

1.If the orchard owner likes only bananas, the banana grower likes only chocolate, and the chocolatier likes onlyapples, will any trade between these three persons take place in abarter economy? How will introducing money into the economy benefit thesethree producers?

2.Why did cavemen notneed money?

3.Why have some economists described money during a hyperinflation asa "hot potato" that is quickly passed from one personto another?

4.Suppose that a researcher discovers that a measure of the total amount of debt in the U.S. economy over the past twenty years was a better predictor of inflation and the business cycle than M1 or M2. Does this discovery mean that we should define money as equal to the total amount of debt inthe economy?