Question 21 What HTTP status code means that the requested file was not found? Question 22 Consider the diagram below. What application-layer protocol is used at position P1 (between the local and remote mail servers)? mail server P1 mail server user agent user agent Mail Sender Local Mail Server Remote Mail Server Mail Recipient Question 23 What do the name and value fields in this DNS resource record represent? clemson.edu. 590 IN NS extns2.clemson.edu. name: value: Question 24 How many bits are in an IP address? Question 25 From the list of protocols below, select all that are transport layer protocols. a. HTTP b. DNS C. ICMP d. UDP e. TCP