Which physical features in canada and the united states could cause barriers for settlers

Many physical features in Canada and the United States could cause barriers for settlers. For example, mountain ranges such as the Appalachian mountaines and the Rocky Mountains could prove to be important barriers. Large rivers such as the Mississippi could also divide regions and make it difficult for settlers to get to some areas. Finally, deserts such as the Arizona desert could prove to be important barriers for settlers.

by using  production possibilities graph.  opportunity costs are key expenses in financial matters and are utilized as a part of registering money saving advantage investigation of a venture. such expenses, be that as it may, are not recorded in the record books but rather are perceived in basic leadership by processing the money costs and their subsequent benefit or misfortune.

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