African Americans contributed to the Union war effort on the home front by working as?

African Americans contributed to the Union war effort on the home front by working as carpenters and surgeons.  In the Union army, more than 179,000 African American men served in over 160 units, as well as more serving in the Navy and in support positions.

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