We pick m.root-servers.net, one of the 13 root servers (1), and ask it about par03s03-in-f7.1e100.net and learn that net is delegated to 13 name servers (2), so we ask e.gtld-servers.net where we learn that 1e100.net is delegated to four name servers, including ns1.google.com (3), so we ask that one and get the following answer: