A wideband speech signal used in VOIP (Voice Over IP) is considered to have bandwidth 50-7000 Hz, and is sampled at 16 kHz. b. Assume that SNR = 6m - 12 (with answer in dB, where m = number of bits used in quantisation of each speech sample), and that we require a high quality voice service with SNR=42 dB. If there is no further compression applied to the digital signal after quantisation, what bit rate do we require to achieve this? (Show all your calculations clearly.) (5 marks) c. Suppose we had a communication channel available to carry the above stream of data, and it had a bandwidth of 15 kHz and SNR=10 dB. Use Shannon's equation to determine if it is theoretically possible to support the high quality voice service on this channel. (Show all your calculations and any estimates you make clearly.) (5 marks)