Perhaps it's just a bias to my personal experience, but a lot of my African American friends have last names like Jefferson and Washington. Was it common for freed slaves to change there last names, and did they often pick the last names of prominent Americans?
Please note: "Many presidents had slaves and slaves took their owner's last names" is not a sufficient answer to this question.
If you have an actual answer that you would be able to back up, with sources if requested, then please feel free to comment. Otherwise, please refrain from doing so.
hi! other responses are welcome, but fyi, you can get started in this section of the FAQ, particularly the last 3 posts, under the heading North America