Suppose the window size is 3.

For Go-back N (GBN) answer following:

 (a) List all the possibilities for the receiver's next expected sequence number, when the sender's window is currently [401, 402, 403]. 

(b) Suppose the receiver's next expected sequence number is 401. List all the possible ranges for the sender's window. 4. 

For  Selective Repeat  answer following:

(c) List all the possible ranges for the receiver's window when the sender's window is currently [501,502, 503]. 

(d) List all the possible ranges for the sender's window when the receiver's window is currently [501,502,503].