Problem: What type of thing is the question "What enigmatic U.S. vice president was once tried and acquitted for treason in a plot to set up his own independent empire in the West ?" asking about?
Answer: human

Problem: What type of thing is the question "Who is Langston Hughes ?" asking about?
Answer: human

Problem: What type of thing is the question "Where is Los Vegas ?" asking about?
Answer:
location