How to do this chemistry question?

Can someone tell me how to solve this question, please explain what you did and why: For a small number at the bottom of a compound, I have put an apostrophe before it e.g. H'2O 1.Sodium nitrate is made from sodium hydroxide and nitric acid. NaOH = HNO'3 --> NaNO'3 + H'2O Calculate how much sodium nitrate will be made in grams when 0.2 moles of NaOH are reacted?