13.
Explanation
1. Noisy Channel:
◦ A noisy channel is characterized by the presence of interference, distortion, or random variations that can corrupt the transmitted signal, leading to errors or loss of information during communication.
2. Noiseless Channel:
◦ A noiseless channel is free from interference or distortion, providing a clear and reliable path for the transmission of signals without the introduction of errors or degradation in the quality of the communication.