Fluoride is an anion of Fluorine
What this means is that the two have the same number of protons (9), but Fluoride has 10 electrons compared to Fluorine's 9.
So the answers are:
Protons - 9
Neutrons - 9
Electrons - 10
Atomic Number - 9
Atomic Mass - 19 g/mol
The answer is a cation, I may be wrong but cation is plus and anion is subtract
C and A because the product of a matter will always be the same and just google A.