Who was the president of the United States during years of the civil war and any did he decide to go to war with the south?

Abraham Lincoln

Explanation:

Abraham did because he did not like the idea of the confederate states and the whole break up thing

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

profound political, administrative, and social changes in the british isles.