Answer 1

Ah, so you mean which to calculate first?
% is ranked like division or multiplication. If you have several of these in a row, they'll be evaluated from left to right.
Whenever you need to figure out the order of operations in Python, this is your go-to source:
https://docs.python.org/3/reference/expressions.html
Scroll down to 'operator precedence', there you'll find it all.
Watch out: Starting from slowest. 😉

Answer 2

You may have to modify the acronym to "Please Excuse My Dear Mad Aunty Sally," with the Mad being added to represent modulo.

Answer 3

Błack Jesus❕ 👍

Answer 4

Whenever you need to know if something is cleanly divisible.
if n%2==0: print('even')
Or when you want to know what remains after you divided.
cookies_left = cookies%number_of_persons
% is a partner of //.
Let's say you have 29 cookies and want to share them among 3 people, but you can't break any cookie.
per_person = 29 // 3
Everybody gets 9 cookies.
How many cookies will be left over?
cookies left = 29 % 3
2 cookies.

Answer 5

Solve the bracket first then multiply the result with A, then take % and subtract 9 from the final result.