Consider the following relation: Problem 2) Fill in the missing entries in the table below. For the "Superkey" and "Key" columns, write "no" if you can rule out that possibility for the given attribute set, write "?" if you can't, and write "yes" only if you can prove that attribute set is a key/superkey (hint: there is a special property that lets us say "yes" in one of the cells). Make sure to include the empty set in the Proper Subsets, but remember the empty set is not considered a superkey. Some cells have been given as an example