3. (a) Explain the main differences between creational, structural and behavioural software design patterns. [7 Marks] (b) The Singleton is an example of a creational software design pattern. In relation to this pattern, provide the following: (i) The Intent of the pattern. [3 Marks] (ii) A description of a context in which the pattern could be applied. [3 Marks] (iii) An example of the code that would implement it. [4 Marks] (c) Identify the category that the following two design patterns belong to and for each one explain their intent and design. In your answer, use UML to show their structure and provide an example use. (i) Adapter [8 Marks] (ii) Decorator [8 Marks]