Reliable Communication, Selective Repeat and Go-Back-N Answer true or false to the following questions and briefly justify your answer. Assume a window size of six. (a) For the selective repeat protocol, is it possible for the sender to receive an ACK for a packet that falls outside of its current window? (b) For the Go-Back-N protocol, is it possible for the sender to receive an ACK for a packet that falls outside of its current window? (c) Please discuss (drawing a timing diagram) a use-case example of a stop and-wait protocol failure in presence of timeout but without sequence numbers. Now discuss (drawing a timing diagram) a failure of the protocol with sequence number but without timeout