Assume statements S1 and S2 defined as: S1: L2-L1 is recursive enumerable where L1 and L2 are recursive and recursive enumerable respectively. S2: The set of all Turing machines is countable. Which of the following is true?

Which of the following language accepted by a Push down Automata?

Consider the grammar given below E? E+E | E*E | E-E | E/E | E^E | (E) | id Assume that + and ^ have the same but least precedence, * and / have the next higher precedence but the same precedence and finally ^ has the highest precedence. Assume + and ^ associate to the left like * and / and that ^ associates to the right. Choose the correct for the ordered pairs (^,^), (-,-), (+,+), (*,*) in the operator precedence table constructed for the grammar.

Given the following statements: (i) Recursive enumerable sets are closed under complementation. (ii) Recursive sets are closed under complements. Which is/are the correct statements?

Which of the following conversion is not possible (algorithmically)?

If P & R are regular and also given that if PQ=R, then?

Grammar that produce more than one Parse tree for same sentence is ___________

Assume the statements S1 and S2 given as:

Grammars that can be translated to DFAs is ___________

The context free grammar S → A111|S1, A → A0 | 00 is equivalent to _________