Question: What instrument does the artist nominated for "Believe Acoustic" use?
Answer(s):
answer: Vocals

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:award.award_nominee.award_nominations ?k .
?k ns:award.award_nomination.nominated_for ns:m.0pb8twh . 
?c ns:music.group_member.membership ?y .
?y ns:music.group_membership.role ?x .
}