About version number in install desittination folder

Today I installed RAD Studio 10.4, The default installation folder is C:\Program Files (x86)\Embarcadero\Studio\21.0\.

I have some questions to ask about this.

(1) Why the RAD Studio version is 10.4, but the version in folder is 21.0, not 10.4?

(2) If 10.4.1 released in future, after upgrade, the folder will still be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?

(3) If I uninstall RAD Studio 10.4, then install 10.4.1, the folder will be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?