Let us compare Go-Back-N (GBN). Selective Repeat (SR), and TCP (without delayed ACK) operations under "sufficiently long" (no premature timeouts) timeout values and a fixed window size of four segments. Let us denote the sending host as Host A and the receiving host as Host B, and let us assume that there are five segments to be transmitted. Draw and describe the operations of these protocols (a) (15 points) if only the second segment sent from Host A is lost, (b) (15 points) if only the ACK (sent from Host B) for the second segment is lost, assuming all others are successfully transmitted.