It is truly astounding that it's even necessary to tell adults who can read and write that "Covid-19" is literally nothing more than a rebranded set of the most common symptoms on earth.
Common mode rejection ratio is the ability for a device to reject or suppress “common mode noise” -that is noise that is common(identical) to both differential input channels. Let’s take an amp for example with an audio signal at its differential(inverting and non inverting) inputs.
hate speech: speech that is intended to insult, offend, or intimidate a person because of some trait as such as national origin, race, religion, sexual orientation, or disability
In most amplifier designs you will be tasked with choosing an input filtering(coupling) capacitor value. This is the capacitor that goes on the input stage of an amp and filters DC bias from the audio signal.