Exercise-1: If the 20 kHz signal is under-sampled at 30 kHz, find the aliased frequency of the signal. Exercise-3: An analog Electromyogram (EMG) signal contains useful frequencies up to 3000 Hz. i. Determine the minimum required sampling rate to avoid aliasing. Exercise-2: Avoice signal is sampled at 8000 samples per second. i. What is the time between samples? ii. What is the maximum frequency that will be recovered from the signal