Answer:
A iii. & B v.
Step-by-step explanation:
The first question is answered thanks to the Law of Conservation of Mass. Because this is simply a process of dissolution, no new substance is formed and the mass of the solution is equal to the mass of water added to the mass of sugar: 100.0 g + 180.0 g = 280.0 g
To answer the second question, you can imagine yourself doing a similar process: No matter how many spoonfuls of sugar (or salt) you add to a glass of water, the volume of the resulting solution will not significantly increase. Thus the volume of the solution will be much less than the sum of the volume of water and the volume of sugar.