How many railway lines go through the station maintained by Public transport authority of western australia?
SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/owningOrganisation> <http://dbpedia.org/resource/Public_Transport_Authority_(Western_Australia)> . ?x <http://dbpedia.org/ontology/servingRailwayLine> ?uri  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/RailwayLine>}
Public_Transport_Authority_(Western_Australia)