Asignal m1(t) is band-limited to 3.6khz, and three other signals – m2(t), m3(t) and m4(t) are band-limited to 1.2khz each. these signals are to be transmitted by means of time division multiplexing. the scheme below shows how the multiplexing requirement may be accomplished. a) determine the nyquist rate for each signal b) what must be the speed of the commutator (in samples per second)? c) if the commutator output is quantized with l=1024 and the result is binary-coded. what is the output bit rate? d) determine the minimum transmission bandwidth of the channel.