Market failure implies that the market mechanism:.

Leads the economy to the wrong mix of output

Explanation:

Market failure is the when there is an inefficient distribution of goods and services in the free market.

One of the types of market failure is externality

Externality is when the production or consumption activities of economic agents have effects on people not involved in the economic activity. Externality can either be positive or negative

A good has positive externality if the benefits to third parties not involved in production is greater than the cost. an example of an activity that generates positive externality is research and development. Due to the high cost of R & D, they are usually under-produced. Government can encourage the production of activities that generate positive externality by granting subsidies.

A good has negative externality if the costs to third parties not involved in production is greater than the benefits. an example of an activity that generates negative externality is pollution. Pollution can be generated at little or no cost, so they are usually overproduced. Government can discourage the production of activities that generate negative externality by taxation  

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answer; swot analysis;