Light dependent reactions oxidize water and make ATP and NADH in the process. This part of photosynthesis could continue to Occur in the aforementioned example. However, for the light independent reactions, carbon dioxide is needed as a reactant to make glucose , so the Calvin Cycle will not continue and the plant would die when it runs out of glucose.
You would place the baseball into water that has already been measured. Then, find the difference(subtract) between the new water level and the old water level.Hope this helped