Answer:
Devido à sua grande extensão, de norte a sul do globo e as formas de relevo com grandes altitudes, como a Cordilheira dos Andes e os Montes Apalaches, por exemplo.
Explanation:
Are those suppose to be words?
The chronometer is a device to measure time in a period of time, therefore not a correct answer.
Answer:
Not 100% sure but I think its the Barail Range. This would affect them by the mountain acting almost like a barrier between them. So they didn't have much interaction.

(simplify the equation)

(subrtact both sides by 14)


(multiply both sides by 6)

Hope it helped,
Happy homework/ study/ exam!