XML Data Format: Derive and test a DTD following these steps. 1. Reduce the class diagram to those classes and attributes, associations and cardinalities required by the scenario. Justify for every element of the class diagram your decision to keep or drop it, always referring to the requirements of the scenario.

marks] 2. Create an XML­specific class diagram and justify the chosen document structure using

the requirements from the scenario.

marks] 3. Derive the DTD and justify the style of mapping for the attributes you have chosen. Is the mapping from the class diagram in 2 to the DTD data preserving? Please justify

your answer, and if the mapping is not data preserving, provide a valid object diagram or XML instance as a counterexample.