Plz Help Quick Canada and the United States both have

A economic barriers that severely limit the importing of products from Mexico.

B separatist movements among their French-speaking people.

C major ports on both the Atlantic and Pacific coasts.

D superpower status in the world at large.

Magma is outside the volcano  and lava is inside the volcano. 

Historians are researchers of the past or people who understand the history of people. with this field, they must possess qualities such as being unbiased, patient, efficient reader, has a knack for logic and critical thinking and reasoning, disciplined, open-minded, resourceful, with good analytical ability, good reasoning skills and problem solving!