What was the job of Buffalo Soldiers? (5 points)

The Buffalo Soldiers' main duty was to support the nation's westward expansion by protecting settlers, building roads and other infrastructure, and guarding the U.S. mail.

Explanation:

I have included a link to the History channel, as there is a grand slew of information to support information regarding their job and day-to-day duties :).

https://www.history.com/topics/westward-expansion/buffalo-soldiers

i dont know but i need points

that would be the steamboat because none of the other things are forms of transportation