who are the participants in a market system that act in their own self interest and how are those self interests rewarded or achieved in this economic system?

Explain the Law of diminishing marginal utility. use plastic swimming pools in your example

what role does freedom play in capitalism include your answer how the inivisible hand has an impact on a competetive eceonmy

Econmists hypothesize that "nothing is free" what key economic term is discussed that relatees to this concept and give another example to where this statement appplies.