Answer to Question #38621 in Math for Sujata Roy

Question

We are given two context-free languages L1 and L2 and L defined as below
a) L=(0+1)* if L1=L2
b) L=((0+00+000)*(1+11+111)*)* if L1 is contained in L2
c) L=((0(10)*)*(1(01)*)* if L2 is contained in L1
d) L=(00+11+0+1)*(0+00+000)* if L1 and L2 are incomparable
a) As all the conditions relating to L1 and L2 are undecidable we cannot say anything about L
b) L is recursively enumerable
c) L is recursive but not context-sensitive
d) L is context-sensitive but not context-free
e) L is context-free but not regular