there is a white, round spot, about an inch and a half in diameter on my family's new kitchen table. we don't know what it is because we don't use the table very much and don't put many things on it, but it is really stuck on there. what are some ways to remove the spot without harming the table's finish? the only clue we have as to what the spot is is that it looks like maybe something was wet and was set on the table and part of the object (maybe some type of plastic bag) got stuck to the table and wasn't removed with the rest of the object. thanks for any help you can give me.