Question: How many different organizations own the railway lines which are a part of Norfolk Southern Railway?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX res: <http://dbpedia.org/resource/>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE { ?x prop:system <http://dbpedia.org/resource/Norfolk_Southern_Railway> . ?x prop:owner ?uri . ?uri rdf:type onto:Organisation}