Answer 2.8
The formula for channel capacity in a baseband
channel (i.e. the useable bandwidth extends from 0 Hz to B Hz is given by:
Channel Capacity C = 2Blog2M
Thus for 28.8 kbps in 3.1 kHz, the number of
symbol states required M is:
M = antilog228800 / (2 x 3100)
= 22.8 or 23 symbol states