SPSecurity.Runwithelevatedprivileges: Best practice

Download it:
https://sites.google.com/site/sasivalipireddy/home/RunWithElevatedPrivileages_ALL.pdf

1. RunWithElevatedPrivileges?
2. Why can’t we use RunWithElevatedPrivileges in event handlers?
3. Impersonation Improvements in SharePoint 2010 Event Receivers?
4. Best recommended practice use of it?
5. Best recommended practice to use of it in Event Receivers?
6. Best recommended practice to use of it in Feature Receivers?
7. RunWithElevatedPrivileges in visual studio workflows:
8. Is RunWithElevatedPrivileges allowed in sandbox solution?
9. By using which credentials the RunWithElevatedPrivileges will run?
10. Difference between SPSecurity.CodeToRunElevated and SPSecurity. RunWithElevatedPrivileges?