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17. According to Shannon's theorem, the maximum number of bits that can be transmitted on a line increases as B (increases/decreases) or the noise (increases/decreases). 18. Which of the following can be used to increase the number of individual channels of information that can be transmitted on a communications link a) Frequency division Multiplexing (FDM) b) Time division Multiplexing (TDM) c) Code division Multiplexing (CDM) d) All the above 19. (circle one) FDM/TDM/CDM uses orthogonal chip (or chirp) sequences to "modulate" each bit. 20. CDM can be used to spread the signal from multiple users over a wide frequency band. When used for this purpose it is called CDMA. (True/False)