2)Can you write a class without specifying namespace? Which namespace does it belong to by default??

              Yes, you can, then the class belongs to global namespace which has no name. For commercial                products, naturally, you wouldn’t want global namespace

3)H ow can you save the desired properties of Windows Forms application?

   ANS)   .config files in .NET are supported through the API to allow storing and retrieving information. They are nothing more than simple XML files, sort of like what .ini files were before for Win32 apps.