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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

Transitioning countries must take into account the costs of capitalism, because they will experience its as the great depression's and they experience its benefits.

What was gained through the gadsden purchase