$100mL$ of $0\mathrm{.}200M$ aqueous potassium hydroxide is mixed with $100\mathrm{.}0mL$ of $0\mathrm{.}200M$ aqueous magnesium nitrate.

a$)$ Write the complete and net ionic equation for this reaction.

b$)$ What mass of the precipitate forms?

c$)$ Calculate the concentration of the potassium and magnesium ions remaining in solution.