The following diagram describes the architecture development process prescribed by the The Open Group Architecture Framework (TOGAF).  The bi-directional arrows linking each phase to business requirements attest to the importance of gathering and confirming business requirements for each phase.  Describe the individual phases A, B, C, D and E and the types of business requirements (functional, technical, etc.) appropriate to each phase. Why is the validation of business requirements important throughout each phase?  What are the risks to the Enterprise Architecture project if business requirements are not validated? Please use examples to illustrate your answer.