1.The push-pull theory is used by scientists to explain:

A.how people fight
B.mountains
C.immigration
D.Farming methods

I think Its either B or c

im dope fake teacher

Which one?

Hm, I think its B

What pushes and pulls mountains?

so farming methods?

and also, ms.sue are you a teacher?

because your always on

No. Two of your guesses are wrong. You're on your own now. Please consider Damon's answer and this website.

http://lewishistoricalsociety.com/wiki2011/tiki-read_article.php?articleId=28

Do not post this question again.

Yes, I'm a teacher.