Answer the following questions: 1. How does a station using CSMA protocol knows that a collision has happened (2 marks)? 2. If we want to digitize a low-pass & KHz voice signal and send 4-bits per sample. What should be the minimum channel bandwidth? (2 Mark) 3. Give examples of two controlled access protocols (2 Marks) 4. Give example of two error correction methods (2 Marks) 5. An analog signal has a data rate of 10000 bps and a signal rate of 2000 baud. How many signal elements are required? (2 Marks) Use the editor to format your