Question: How many people have been presenters for NBC shows?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE { ?x onto:channel <http://dbpedia.org/resource/NBC> . ?x prop:presenter ?uri  . ?uri rdf:type onto:Person}