How many {stock exchange} are to/by {NASDAQ} ?
How many stock exchange are by NASDAQ?
SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P414 wd:Q82059 }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P414> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q82059 .
} 

Let me know the number of stocks exchanged by NASDAQ?