Answer:
b. the marginal social benefit to exceed the marginal private cost of the last unit produced.
Explanation:
<u>Positive Externality-</u>
Positive Externality occurs when production or the consumption or of the good causes benefit to the third party. 
For example, when the individual consume education in order to be uplifted and get a benefit but this education also benefits the society by uplifting the whole society.
<u>Positive externality causes the marginal social benefit to be greater than the marginal private benefit.</u>
 
        
             
        
        
        
Most, but not all, sociologists agree that it is unethical to misrepresent themselves.
In any type of investigation, it is important that the researcher identifies himself, the purpose of his investigations and requests the consent of the respondents. The sociologist and other researchers will question the idea of full disclosure during the investigation, citing changes in respondents. As sociologists study social patterns and relationships, it is expected that respondents in a sociological study will only present information that is considered socially acceptable, taking care of the political and cultural context of their points of view. For the sociologist, it is important to have a complete disclosure and to convince respondents to provide honest answers, that´s why its important to never misrepresent themselves, to be taken seriously.
 
        
             
        
        
        
I believe the answer is: proximodal trend
Proximodal trend refers to the period when children started to develop more specific muscle/ motor skills.
For people in general, our upper body tend to be developed at much faster rates compared to our lower body, which cause infants having to crawl first before they are able to walk.
        
             
        
        
        
Social Darwinists still believe the survival of the fittest.
So they believe the one that stuck in poverty are the one that is not fit well within the society
hope this helps
        
             
        
        
        
Answer:
All countries were impacted by the invention. Shipping goods
Explanation:
Everybody wears shirts and planes and boats are technology that help with transportation