Figure 1 gives a fragment of the conceptual model for performances by bands at a 3-day music festival. Bands may make more than one performance during the festival. All performances take place on a single stage. The musicians in some bands may not be known at this point in time as some of the bands are re-forming with previous members from years gone by to celebrate the 40th anniversary of the festival. Bands and musicians may have confirmed their appearance, cancelled their appearance, or not yet replied to their invitation. The figure shows just the entityrelationship diagram, the entity types and an additional constraint.

Entity-relationship diagram Is MemberOf Band Musician Performance PlaysA Takes Partin Entity types Band (BandName, Confirmation Status ) Musician ( MusicianName, AgentName, Confirmation Status ) Performance Date, Time) Additional constraint c.1 The Confirmation Status attribute of both Band and Musician can take three possible values: Confirmed, Cancelled, Pending. Figure 3 Fragment from Festival conceptual data model (a) In transforming the fragment in Figure 3 into a corresponding relational representation according to relational theory discussed in Block 2, identify which of the relationships Is MemberOf, TakesPartIn, and PlaysA can be represented by foreign keys alone, and which must be represented by a relation. In the latter case, justify briefly why the relationship(s) cannot be represented by foreign keys alone. If there is more than one reason why a particular relationship cannot be represented by foreign keys alone give all the reasons