Mmm.. I'm not sure if anyone knows this but I seem to have a problem with this undecidability and rice theorem thing:

Let Land L' be languages over the same alphabet. Give example of the following statements:
a) L' is decidable, L is undecidable and L C L' holds (L subset of L')
b) L' is decidable, L is undeciadable and L' C L holds (L' subset of L)

The hint given his : consider languages of Java programs..

How am I gonna do this?