73) If a designer wants to design a point-to-point sub-network with 10 routers of full duplex line, then total number of lines among them would be

74) Maximum data rate of a noiseless 4 kHz channel using T1 PCM system is

75) Phase shift keying (PSK.) method is used to modulate digital signals at 9600 bps using 16 levels. The line signals speed (i.e. modulation rate) will be

76) Television channels are 6 MHz. How many bits can be sent if four level digital signals are used (assume a noiseless channel)

77) What is the maximum burst length on an 155.52 Mbps ATM ABR connection whose PCR value 200,000 and whose L value is 25 msec ?