The parties involved in an externality have an incentive to reach an efficient solution because

The parties involved in an externality have an incentive to reach an efficient solution because all involved are better off when an efficient solution is reached.

An externality is a benefit or cost that affects someone who is not directly involved in the production or use of a good or service. When the solution is solved everyone has a better chance of reaching their goals due to the solution being found.

an aneroid barometer is different from a mercury barometer in that it provides readings that increase as air pressure increases.

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