They don't exist...monopolies are caused by government intervention in the market. Excessive regulations, permits, fees etc. create barriers to entry for competitive entrepreneurs, and there is often times legislation passed in favor of large corporations. A truly competitive free market does not have monopolies.
natural, geographic, technological, government
barriers to entry
Government regulation might be used to facilitate competition.
Monopolies exist for two reasons: 1.) The overhead cost is to high for competition to exist. For example a power company owns all the power lines and necessary equipment to generate electricity for a city. If another company decided to compete it would need to build an infrastructure from scratch resulting in to high of an overhead. 2.) The other reason is when a single entity controls a significant amount of a market resulting in a lack of economic competition.
They are not. Although some like for example con Edison are but, they are a "natural / limited monopoly" in other words they are extremely regulated by the government.
Yes, monopolies exist when a company dominates a particular industry and controls a large portion of the market. This can lead to less competition, higher prices for consumers, and less innovation in the industry. Governments often regulate monopolies to promote fair competition.
natural, geographic, technological, government
When private firms gain monopoly power, usually because of economies of scale, they are in a position to restrict production and raise price with little worry of competition; these are known as natural monopolies.
barriers to entry
Average costs drop as production rises. This is why natural monopolies are possible.
Perhaps not, but evolution can exist without natural selection.
Government regulation might be used to facilitate competition.
Natural plasma exist only at very high temperatures, or low temperature vacuums.
Monopolies exist for two reasons: 1.) The overhead cost is to high for competition to exist. For example a power company owns all the power lines and necessary equipment to generate electricity for a city. If another company decided to compete it would need to build an infrastructure from scratch resulting in to high of an overhead. 2.) The other reason is when a single entity controls a significant amount of a market resulting in a lack of economic competition.
Of course!
Eliminated competition
monopolies were bad