Each DNS resource record is a $4-$tuple: $.$ For questions in this

problem, you can ignore the TTL field. Assume that some domain name server, denoted as

SRVR$,$ only has the following DNS resource records in its database. $($All information listed here

is made up and does not reflect the real case.$)[10]$

$($a$)$ if a local domain name server wants to know the IP address of amazon.com and sends a

query to SRVR$,$ what is the domain name for the domain name server that the local domain

name server will contact next? What is the IP address of this domain name server?

$($b$)$ If a local domain name server wants to know the IP address of cs$.$njit.edu and sends a query

to SRVR$,$ what is the IP address for the domain name server that the local domain name server

will contact next? What is the canonical domain name for this domain name server? What is the

alias for this domain name server?

c$)$ According to the information on SRVR$,$ what is the domain name of the email server that

runs the email server application for the montclair.edu domain? What is the IP address of the

email server?