Prime number checking include multiplication , division and CSL comes here in picture.
a) CSL
b) its complement of (a) which is CSL and CSL is closed under complement so its too CSL
c)Non liner power generally causes to CSL , its CSL.
d) same reason , its CSL
e) again prime number calculation so CSL
f) here he played game, so be careful. an where n is prime or product of 2 or more prime , here if you focus more any number >=2 can me written in that way.
guess any number , it can be factored into prime numbers.
so its actually an where n>=2 so regular
g) its same as f) with NULL included so Regular