8.103 Review the data flow diagramsyou developed for questions in the Petrie Electronics case at the end of Chapter 7 (or diagrams given to you by your instructor). Study the data flows and data stored on these diagrams and decide whether you agree with the team's conclusion that the only six entity types needed are listed in the case and in PE Figure 8-1. If you disagree, define additional entity types, explain why they are necessary, and modify PE Figure 8-1 accordingly.