#2
i assume you mean stuff like 1:22 and 2:10/2:16....those are harmonics acheived by feedback. you hit a note and get close to your amp with lots of gain and it hits a different pitch. It takes some experimenting but you can get different pitches. He can do it without getting close to an amp because of the sheer volume of playing live allows feedback to occur from a ways away.
#3
He might be doing touch harmonics, I use those a lot. Pick a note, then count up a harmonic interval (+5, +7, or +12 frets) and lightly touch the string while it's still vibrating with your tapping finger, but don't fret it. Just touch it, and if you do it right, the note will morph into a harmonic.

However, I think he's just using feedback.
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