Duplicate movie with a time delay

hi all, newbie here trying to learn flash. Was looking at the duplicate movie tutorial and was wondering if there is a way to delay the duplication a certian X time. so, say my MC is a tween that goes for 50 frames… I would like it to duplicate itself at the end of the 50 frames.

Also, at the end of the 50 frames I would like to unload the MC underneath the 1st MC. I know sounds complicated. but simple idea. 1 MC, duplicates itself over top on the first, and then unloads the 1st MC.

if this is not possible, let me know… just trying to figure flash out… trying to see what flash can do, thanks

cheers

norm