Question: Who are the current senators from the place with the official symbol of Quercus?
Answer(s):
answer: Bob Menendez
answer: Cory Booker

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:government.governmental_jurisdiction.official_symbols ?k .
?k ns:location.location_symbol_relationship.symbol ns:m.0hlsd . 
?c ns:government.political_district.representatives ?y .
?y ns:government.government_position_held.office_holder ?x .
?y ns:government.government_position_held.governmental_body ns:m.07t58 .
FILTER(NOT EXISTS {?y ns:government.government_position_held.from ?sk0} || 
EXISTS {?y ns:government.government_position_held.from ?sk1 . 
FILTER(xsd:datetime(?sk1) <= "2015-08-10"^^xsd:dateTime) })
FILTER(NOT EXISTS {?y ns:government.government_position_held.to ?sk2} || 
EXISTS {?y ns:government.government_position_held.to ?sk3 . 
FILTER(xsd:datetime(?sk3) >= "2015-08-10"^^xsd:dateTime) })
}