5. Given a valid instance of a relational schema Friends with three attributes (X, Y, Z), containing the tuples: (monica, 216, 657), (ross, 216, 657), and (phoebe, 657, 657), (chandler, 657, 216). Specify whether each of the following functional dependencies holds over Friends: a. XY b. XZ Y c. XY Z d. YZ X 6. Given a relation R(A, B, C, D, E, F) and a set of functional dependencies F = {AB, BC, ABD, EFA}: a. List 3 super keys for R b. List all candidate keys for R c. List all possible primary keys for R d. List all normal forms that R satisfies