Did global trade benefit or harm the world from 1000-1500 CE?

Will have the greatest effect on human health. pollution in the a. troposphere b. stratosphere mesosphere d. thermosphere

Which of these played the biggest role in increased urbanization in the late 1800s? a) transportation improved b) the military was stronger c) no one was farming anymore d) steam power was discovered

Search america's open door policy with china beginning in 1899. explain how relations with the united states and china have changed and the effects of the open door policy on both countries.