According to johnson, which of the following was the primary reason for the tribes to unite a. to increase trade b. to provide self-defense c. to gain additional land d. to make the tuscarora leaders

I would personally go with letter C

its a map of something

question 10: the answer is c, to their constituents address a problem.

question 11: i think it would be domestic bills, which deal with american issues only and public bills, which affect the whole nation.