Question: Who is the office holder whose deputy was Andrew Peacock and predecessor was Alexander Downer?
SPARQL:
SELECT DISTINCT ?uri WHERE {?uri <http://dbpedia.org/property/deputy> <http://dbpedia.org/resource/Andrew_Peacock> . ?uri <http://dbpedia.org/ontology/predecessor> <http://dbpedia.org/resource/Alexander_Downer>  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/OfficeHolder>}