Questions

Error is in third part. Since “doing” was used in second part it should be followed by “doing” in third part as well instead of using “done”. Such repetitive figure of speech is used in
English grammar to create emphasis. This sentence indicates that a thing that is worth doing is also worthy of doing well. Here worth is the noun that must be followed by the verb doing.

Capitalism is an economic system in which private individuals or businesses own capital goods i.e, economy is characterized by private ownership of the means of production. The production of goods and services is based on supply and demand in the general market known as a market economy and not on central planning known as a planned economy.