$3.$ What is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the client computer and gaia.cs$.$umass.edu? $($Note: this is the $$raw$$ sequence number carried in the TCP segment itself; it is NOT the packet # in the $$No$.$ column in the Wireshark window. Remember there is no such thing as a $$packet number$$ in TCP or UDP; as you know, there are sequence numbers in TCP and that$$s what we$$re after here. Also note that this is not the relative sequence number with respect to the starting sequence number of this TCP session.$).$ What is it in this TCP segment that identifies the segment as a SYN segment? Will the TCP receiver in this session be able to use Selective Acknowledgments $($allowing TCP to function a bit more like a $$selective repeat$$ receiver, see section $3\mathrm{.}4\mathrm{.}5$ in the text$)?$

$4.$ What is the sequence number of the SYNACK segment sent by gaia.cs$.$umass.edu to the client computer in reply to the SYN$?$ What is it in the segment that identifies the segment as a SYNACK segment? What is the value of the Acknowledgement field in the SYNACK segment? How did gaia.cs$.$umass.edu determine that value?

$5.$ What is the sequence number of the TCP segment containing the header of the HTTP POST command? Note that in order to find the POST message header, you$$ll need to dig into the packet content field at the bottom of the Wireshark window, looking for a segment with the ASCII text $$POST$$ within its DATA field $,.$ How many bytes of data are contained in the payload $($data$)$ field of this TCP segment? Did all of the data in the transferred file alice.txt fit into this single segment?

$6.$ Consider the TCP segment containing the HTTP $$POST$$ as the first segment in the data transfer part of the TCP connection.

$$ At what time was the first segment $($the one containing the HTTP POST$)$ in the data$-$transfer part of the TCP connection sent?

$$ At what time was the ACK for this first data$-$containing segment received?

$$ What is the RTT for this first data$-$containing segment?

$$ What is the RTT value the second data$-$carrying TCP segment and its ACK?

$$ What is the EstimatedRTT value $($see Section $3\mathrm{.}5\mathrm{.}3,$ in the text$)$ after the ACK for the second data$-$carrying segment is received? Assume that in making this calculation after the received of the ACK for the second segment. explain please