We pick l.root-servers.net, one of the 13 root servers (1), and ask it about 7.0.0.0.0.0.0.0.0.0.0.0.3.5.0.0.5.0.0.0.8.e.2.0.c.7.6.0.1.0.0.2.ip6.arpa and learn that ip6.arpa is delegated to six name servers (2), so we ask c.ip6-servers.arpa where we learn that 6.0.1.0.0.2.ip6.arpa is delegated to six name servers, including ns3.nic.fr (3), so we ask that one and get the following answer:
Authoritative answer
ANSWER for 7.0.0.0.0.0.0.0.0.0.0.0.3.5.0.0.5.0.0.0.8.e.2.0.c.7.6.0.1.0.0.2.ip6.arpa.