Suppose we have the following relational instances: R(A, B, C) = {(1, 2, 1), (2, 1, 1), (2,3,4)}, SIA, D) = {(2, X). (5,Y)}. 1. A is the primary key of R. State Yes or No. 2. B is a super key of R. State Yes or No. 3. Write the schema of Rx S. 4. Write the instance (all tuples) of Rjoin S. 5. Write the output of Runion S