Explanation:
members of the same species battle each other to protect their young
Alfred Marshal was one of the most influential economists of his time and the author of the Principles of Economics book which was the principal economic textbook in England for long years. During his economic theory development, he borrowed a concept from the marginalists which is the theory of demand and the collective result of buyers who yearns services and products or the concept of scarcity.
Each vaccinated child stops the transmission of the disease. therefore, as long as 90 percent of the people in a community are immunized, no one dies of the disease.
<h3>What is herd immunity?</h3>
The expression herd immunity makes reference to a level of immunization in the population in which people become resistant to the pathogen.
In conclusion, each vaccinated child stops the transmission of the disease. therefore, as long as 90 percent of the people in a community are immunized, no one dies of the disease.
Learn more about herd immunity here:
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