Question 2 Investigate voice over IP. (10 marks) Figure 2 shows the digitizing of Alice's voice signal with Pulse Code Modulation (PCM). Analog signal PCM encoder Sampling Quantized signal Quantizing PAM signal Figure 2. Pulse Code Modulation. Encoding 111100 Digital data Tasks 1. Discuss how the quantization error affects the quality of PCM by comparing 3 bit-depth and 8 bit-depth of sampling. (4 marks) 2. Draw a flowchart to show the quantization process. (3 marks) 3. Further investigate the sampling theory, and explain how the A/D conversion quality relates to the resources consumed. (3 marks)