What can be concluded from the union's desire to blockade ports in the south?

a. the union navy was large and effective.

b. southern port cities were also industrial centers.

c. foreign nations were willing trade partners with the confederacy.

d. no foreign nations were willing to assist the confederacy.

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.