2 - 3 hours is ample time.

Adults 19-64 yo $13 Adults 65 and older $9 Children 3-18 yo $6 Under 3 yo Free

This is not a question about visiting the museum. It is a policy question and should be directed to the museum itself. It political in nature. I can answer questions on parking, the exhibits shown, the educational programs offered, etc. I cannot answer policy questions about artifacts that have been returned to a country or the museum's policy on maintaining artifacts found during digs in other countries.