Answer: The answer to the first one is the second option and the answer for the second one is the first option.
Explanation:
1) it explains about stability of an atom by including stationary state.
2) it explains tge quantization of energy.
3) it gives the concept of angular momentum of a revolving electron.
Following the Law of Conservation of Mass, you simply add the mass of both substances. Thus, 160 grams + 40 grams = 200 grams. So, even if initially, they are in liquid and solid form, they would still have the same mass even if they change phases, owing to that they are in a closed space.
