C seafloor spreading at mid-ocean ridges
He postulated that all the continents were once joined together in a single landmass and had since drifted apart.
He stated in his book that " the Mid-Atlantic Ridge ... zone in which the floor of the Atlantic, as it keeps spreading, is continuously tearing open..."
It was the first agreement for self-government to be created and enforced in America.
Since 1790 US has more than doubled in size and has more than ten times the population.
Explanation:
During the 1790's census some of the most surprising facts that can be known are that
-There was no Alaska as a part of the US and no other foreign territories were a part either. A large part of the west coast was either under Mexican control or not taken up by any powers and made simply home by the natives.
-These places were all settled later in the next century and by the end of that century the population had expanded many times over
-The coastal population on the west is many times more than the total population of US in 1790.
Trade barriers restrict or reduce international trade which reduces international cooperation among states and the overall interdependence. For example, if you rely on another country to buy cocoa and they rely on you to get sugar, if you enact trade barriers, you won't get cocoa and they won't get sugar which will be a huge problem for both industries in both countries because you depend on each other.
