what is the {end time} for {Zeno} has {position held} as {Byzantine emperor} ?
For how long was the Byzantine Empire ruled by Zeno?
How long did Zeno ruled the Byzantine Empire?
SELECT ?k WHERE { ?l property:end_time ?k . ?l property:position_held resource:Byzantine_emperor . resource:Zeno property:position_held ?l }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q183452> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P39> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q18577504> .
?statement <http://www.wikidata.org/entity/P582> ?value. 
} 

SELECT ?value WHERE { wd:Q183452 p:P39 ?s . ?s ps:P39 wd:Q18577504 . ?s pq:P582 ?value}