A few question on optimizing the code

1. Does comments in code affect the processing time on server?

2. Do I decrease the process time if I change <asp:Label></asp:Label> to <asp:Label />

3. Is there a difference in writing "using System.Web.Security;" at the beginning of the code or
 specifying it when it is needed "System.Web.Security.FormsAuthentication.SignOut();"

4. Should I spend more time on trying to reuse connections if possible when processing the page.
   Someone said that .NET does this automatically if the use of the connection happens within a certain time?

5. Does formatting and long variable/function names affect the processing of the page and is it worth anything to shorten them?

Thanks in advance!

/zalk

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