machine_question: what are the 7 countries that are part of central america and the currency used in the country is United States Dollar
question: Which of the seven Central American countries uses the United States Dollar currency?
sparql: PREFIX ns: <http://rdf.freebase.com/ns/>
  SELECT DISTINCT ?x
  WHERE {
  FILTER (?x != ns:m.01tzh)
  FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
  ns:m.01tzh ns:location.location.contains ?x .
  ?x ns:common.topic.notable_types ns:m.01mp .
  ?x ns:location.country.currency_used ns:m.09nqf . 
  }
webqsp_question: what are the 7 countries that are part of central america