For example: we have registered domain name **domain.com** and added
name server records at the registrars server:  

ns1.domain.com.  

ns2.domain.com.  

ns3.domain.com.  

Than we look up for **domain.com**. We get all 3 name server adressess.  

1. Which one of that servers will be requested further and why?  

2. Do the order of NS records in the zone file matters?  

3. Is it determined in any **RFC**?