Question

How will the addition of water affect the acidity of a highly acetate solution having pH 2

Answer 1

By common logic you know that water has pH=7
When you add water to something that is acidic, for example you add water to vinegar, you make it less acidic. So the pH from 2 will be higher for instance 3 or 4 or 5 etc.
This happens because pH=-log[H3O+]