Need help with following answer

Question

Hi all,

1 Why C# class does not support multiple inheritance where interface support??? Pls somebody give me the specific reason. 

2. In real scenario where to use abstract class and where to use interface????

3. Why asp.net web.config file is xml based file????

4. When to call dispose method, when to call finalize method and when to call destructor method ???

5. What is the prior condition to store custom value in viewstate????

6. In real scenario when to use static constructor??

Pls somebody give me the most appropriate answer..thanks in advance...