What barriers made it hard to trade in ancient China?
Please list 3 answers, thank you!
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An externality can be created by a. people working at a production job and enjoying their work b. a production activity but not a consumption activity c. a consumption activity but not a production activity d. a production activity or a consumption activity externalities a. are always positive, and an example is flu vaccinations b. are always negative, and an example is the pollution created by trucks c. can be negative or positive. logging has a negative externality, and education has a positive externality d. can be negative or positive. a negative externality is having to go to school when you would rather go to the beach, and a positive externality is spending time with your friends

What’s the reason for not digging up aztec ruins in modern mexico city

When pay is made public, people evaluate how equitable their pay is in light of the pay other people are receiving. the problem in this case is that dwight and guillermo have found out that others are getting paid more than they do for the same work. what are they likely to do under these circumstances