Which best describes an opportunity cost

Which four of these developments were made under mongol rule during the pax mongolica? the extension of the grand canal in china the spread of christianity the spread of weapons that used gun powder the invention of new medicines the establishment of a postal system the invention of geometric models of lunar motion

Select the correct answer.when alexander the great ruled his empire, he spread greek culture and increased his empire's wealth. along the way, he founded many cities, most of which he named after himself. review the following map. how did alexandria's location affect trade? a. it forced people to rely on shipping to trade with other nations. b. it brought together people from the west and east for trade. c. it led to conflicts between regions of the empire. d. it forced people to pay tribute to alexander as their leader.

What is the definition of evolution