When historians want to evaluate a primary source in the form of human remains, they send the remains to These professionals study the remains and share their knowledge with historians. When historians want to locate a written source about
an ancient human culture, they may ask
These professionals help historians find books on the subject written by
reliable authors.

What two different approaches did the knights of labor and the american federation of labor take in building a union organization? a) the knights of labor accepted only unskilled workers; the american federation of labor accepted only skilled workers. b) the knights of labor accepted skilled and unskilled workers; the american federation of labor accepted only skilled workers.c) the knights of labor refused to accept african american or chinese workers; the american federation of labor accepted all workers.d) the knights of labor accepted workers from a single industry; the american federation of labor accepted workers from several industries.