How do you set the saw 'set'?

It is the displacement of teeth on the saw, i.e., to bend the teeth of the saw alternately to either side of the blade. ( then I noticed this is in a computer section, sorry).

The set on the teeth makes the kerf (width of the cut) slightly wider then the blade so the saw can clear the dust from the cut and the blade won't bind up.

No. Let A = {a} (a singleton set) then P(A) = {a, 0}where 0 is the null (empty) set.

Speaking in a grammatical sense, one sets a precedent, not a precedence.

when the sun/moon appears to slowly meet the horizon and disappear