A PAM telemetry system involves the multiplexing of four input

A PAM telemetry system involves the multiplexing of four input signals: si (t), i = 1, 2 3, 4. Two of the signals s1 (t) and s2 (t) have bandwidths of 80 Hz each, whereas the remaining two signals s3 (t) and s4 (t) have bandwidths of 1 kHz each. The signals s3 (t) and s4 (1) are each sampled at the rare of 2400 samples per second. This sampling rate is divided by 2R (i.e., an integer power of 2.) to derive the sampling rate for s1 (t) and s2 (1).
(a) Find the maximum value of R.
(b) Using the value of R found in part (a), design a multiplexing system that first multi-plexes s1 (t) and s2 (t) into a new sequence, s5 (t), and then multiplexes s3 (t), s4 (t), and s5 (t).