I am having some confusion in understanding RICE's theorem.It says every non trivial property of RE in undecidable.I need to understand when to apply RICE's theorem and when to not.Questions like:- Turing machine makes at least five moves,It  accepts a string input of length atleast five ,TM halts for every input on length <50 are all decidable.But these are NON TRIVIAL properties?Some TM will make 5 moves and some will not,Some will halt on every input <50 and some will not?So if this is Non trivial property then why cant we apply RICE's theorem?On other side questions like:- TM accepts at least 10 strings is undecidable because some TM will say yes and some will say NO.Then why can't we use same concept on above mentioned questions?Please help me in understanding how to identify whether question is based on Rice's theorem or not?
RICE theorem applications
rice theorem