2) Adding a capacitor and a resistor is a safety precaution to guarantee that when the circuit is plugged into a speaker or headphones that they don’t blow up.
4)Photo of non-inverting: https://drive.google.com/file/d/1jiIcjYFjp55RPm_zvC8SngvH0PsncvAA/view?usp=sharing
a)Gain = 2 = 1+R2/10k
R2 = 10k
Video of Potentiometer non-inverting:
https://drive.google.com/open?id=1rQOORIrjTcxn5UxNUGbAWNpbEPFOgbx8
Gain max = 2 = 1+10k/R1
Gain min = 1 = 1+0/R1
R2 = 10k
b)Photo of inverting:
https://drive.google.com/open?id=1abFeA_NpK5L-reJD2jyfcHGWN6daDVOe
Gain = 2 = Rf/10k
Rf = 20k (about 22k)
Video of inverting Potentiometer:
https://drive.google.com/open?id=1vvIrU-iAJbNBIfEr16US0qrKuURy5Zie
Gain max = 2 = 10k/Rin
Gain min = 0 = 0/Rin
Rin = 5k
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