Flash mx - unloading movieclips

Scene 2 in my movie loads an external clip with following code:
loadMovieNum(“clips/menu.swf”, 1);

…and another movie with:
loadMovieNum(“clips/globe.swf”, 2);

I also have separately on one of the layers in scene 2 a Back button and an Exit button.

When I want to move back to scene 1 or Exit the “globe.swf” remains loaded. The options loaded from “menu.swf” into level 2
don’t disappear either.

What is the code/solution to make them disappear using the Back and Exit buttons?

Thanks your help
kleb