In u. s. history, 19th century use of the term "american frontier" refers to
a) the area where pioneer settlement ended.
b) the atlantic or pacific coast of north america.
c) the territory east of the appalachian mountains.
d) any territory beyond the thirteen original colonies.

Which statement describes the primary purpose of the european union? question 1 options: to protect european nations in the event of another world war to work together to strengthen europe and benefit all member nations to prevent alliances from forming between member nations to share resources and make economic trade easier between coal and steel companies