Question: What is the country that has an airport that serves Kleve (district)and that uses the euro as its principle currency?
Answer(s):
answer: Germany

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.02l6h)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.02l6h ns:finance.currency.countries_used ?x .
?x ns:base.biblioness.bibs_location.loc_type ?sk0 .
FILTER (str(?sk0) = "Country")
?x ns:location.location.contains ?c .
?c ns:aviation.airport.serves ns:m.01b98m . 
}