25. All of the following are important reasons output per person in the United States is much higher than it was a century ago except: A. the fraction of the population that is working is much greater. B. the skills, equipment, and infrastructure the typical worker has to work with are much greater. C. we are able to produce much more from a given amount of capital and labor. D. the premise of the question is incorrectoutput per person in the United States today is not much different than it was a century ago