What is {population} of {Aden} that is {determination method} is {estimation process} ?
How many people do currently live in Aden?
What is the current population of Aden?
SELECT ?o WHERE { ?h property:determination_method resource:estimation_process . ?h property:population ?o . resource:Aden property:population ?h }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q131694> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1082> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P459> <http://wikidata.dbpedia.org/resource/Q791801>
} 

SELECT ?obj WHERE { wd:Q131694 p:P1082 ?s . ?s ps:P1082 ?obj . ?s pq:P459 wd:Q791801 }