What is an externality? someone who wouldn't choose to pay for a certain good or service but who'd get the benefits of it anyway
if provided as a public good someone who would choose to pay for a certain good or service but does not get the benefits of it if provided as a public good a shared good or service for which it would be impractical to make consumers pay individually and to exclude nonpayers a side effect of a good or service generating benefits or costs to someone who doesn't decide how much to produce or consume?
An externality is defined as the cost or benefit that affects a group when the group did not choose to receive that cost or benefit. This results in either a position or negative consequence based on what happened to a third party that was not origionally involved.
Someone who wouldn't choose to pay for a certain good or service but who'd get the benefits of it anyway is the best definition given to be the answer to this question.
The order of operations is necessary for simplifying numerical expressions because it ensures that the expression is simplified correctly through a series of steps proven to be efficient in simplification.