Suppose you analyze two stations interconnected by a half duplex line with a capacity of 1 Mbps and a propagation time of 5 ms. These stations use to communicate a HDLC BA 3 protocol with the maximum possible transmission window size (non-extended control field and CRC of 2 bytes), and a timer of 10ms. Consider that the control frames are of negligible length and negligible processing time. Consider the minimum transmission time of a control frame to be 1ms and set the minimum transmission time of a data frame to the nearest millisecond. Determine: a) Determine the MTU (maximum transmission unit) of the protocol knowing that the frame efficiency is 96% with respect to useful data (without considering delimiters). b) Represent the frame exchange for the case of sending 5 frames from one station to another. (specify the time represented by the line spacing) c) Represent the frame exchange for the case of sending 5 frames from one station to another, taking into account that an error occurs in the fourth frame transmitted for the first time.