An ECG device in Europe must remove 50Hz interference Suppos

An ECG device (in Europe) must remove 50-Hz interference. Suppose that this is done with a digital HR notch filter whose frequency response is shown in the figure. Determine the sampling frequency used when the ECG was recorded.

Base sampling period is 2*pi for 50Hz
Actual sampling period is (pi/2)-(pi/2)=pi
(1/(2*pi)) for 50Hz
(1/pi) for =((1/pi)*50)/(1/(2*pi))=100Hz