Answer:
There were multiple.
Explanation:
(If you are referring to the Secretary of Treasury)
Louis McLane was the first. However, Jackson replaced McLane with William J. Duane. Shortly after Duane took the position, Jackson fired him and replaced him with Roger B. Taney. At the end of Jackson's presidency, there was also Levi Woodbury.
The Answer is B: Mexico ceded more than a half of its territory.
African Americans had new employment opportunities as men went away to fight in the war. However, they still had to fight for civil rights, as seen by leaders like MLK or Malcom X.
I think it's C. But I don't really know... Hope this helps!! :)