Question: Which US President during the time when Sean Stackley's office was established?
Answer(s):
answer: John Adams

SPARQL query:
#MANUAL SPARQL
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT  ?x
WHERE {
?c ns:government.governmental_body.members ?k .
?k ns:government.government_position_held.office_holder ns:m.064phn1 . 
?c ns:organization.organization.date_founded	?d . # United States Department of the Navy
  ns:m.060d2 ns:government.government_office_or_title.office_holders ?y . # President of the United States
  ?y ns:government.government_position_held.from ?from ;
     ns:government.government_position_held.to ?to ;
     ns:government.government_position_held.office_holder ?x .
  FILTER(xsd:dateTime(?from) - xsd:dateTime(?d) <= 0)
  FILTER(xsd:dateTime(?to) - xsd:dateTime(?d) >= 0)
}