Discuss how and why various groups of people within American society began to challenge and criticize the nation’s way of life in the 1960s. Were their criticisms valid? What were some of the goals of these groups, and how did they go about achieving them?

1.a)britain

2.b)spain

3.c)french

4.d)portugal

explanation:

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain

to extend a country’s power and influence