Answer :

Hi.  Fruit Punch is a solution and i know this because in a Fruit Punch, you have to mix water, the fruit juice, sugar and many other substances. In pure water it is just water. In cereal and milk, those are two different foods, not a combined one, like Fruit punch. Hope that was not too confusing! ;)
Fruit punch is because it blends together evenly and cereal and milk in a bowl you can't mix together you could easily take the cereal out and for the fruit punch you cant