Remarks by Vice President Harris in Moderated Conversation Following Her Historic Trip to Africa   National Museum of African American History and Culture Washington, D.C. 4:39 P.M. EDT THE VICE PRESIDENT: Good afternoon, everybody.  (Laughs.) AUDIENCE:  Good afternoon! MS. NABONGO:  Good afternoon. THE VICE PRESIDENT:  Good afternoon. MS. NABONGO:  It’s so nice to see you in D.C. — THE VICE PRESIDENT:  I know. MS. NABONGO:  — after seeing you …