Final answer:
The inside portion of a soup bowl, typically bread, is consumed while eating the soup, not removed separately. Sugar cubes placed in a bowl within a water dish on a table will likely dissolve due to sugar's hygroscopic nature, making storage in such a way impractical.
Step-by-step explanation:
Regarding the question of when the inside, cut portion of the soup bowl is removed, the traditional approach in dining etiquette is that the bread or cut portion inside a soup bowl (often referred to as a bread bowl when the soup is served inside a hollowed loaf of bread) is generally eaten while eating the soup. One doesn't remove it before serving, after finishing, or discard it entirely; it's part of the meal to be enjoyed with the soup.
In relation to predicting if sugar cubes in a bowl placed in a dish of water can be stored on a table, this would generally not be advisable. Sugar is hygroscopic, which means it absorbs moisture from the environment. If the bowl of sugar cubes were to sit in a dish of water, the sugar would quickly absorb the water and dissolve, leading to a messy dissolution of the cubes. Therefore, storing sugar cubes in a bowl placed in a dish of water on a table is impractical and likely to end in a soggy mess.