I have the following questions about using the .Net framework:

1. To improve performance when starting apps, is it possible to preload the .Net framework at boot time, and keep it in RAM for a few minutes after closing an application so that Windows won't have to fetch the framework from disk?

2. Are .Net apps hard-coded to use a specific version of the .Net, so we must keep all versions installed on disk, or are applications version-agnostic and will simply load the latest framework installed?

3. Is it possible to sign the framework and tell antivirus applications to stop checking it when loading an application?

Thank you.