5. [20 points) Consider a relational schema R(A, B, C, D, E) with the following set of dependencies: F={ ABC, BD, CD+E, EA} (a) List all candidate keys of R. (b) Indicate all BCNF violations. (c) Give a lossless-join decomposition into BCNF for schema R. (d) Indicate which dependencies, if any, are not preserved by your BCNF decomposition in (c)