## Automata Theory Questions and Answers Part-6

1. δ*(q,ya) is equivalent to .
a) δ((q,y),a)
b) δ(δ*(q,y),a)
c) δ(q,ya)
d) independent from δ notation

Explanation: First it parse y string after that it parse a.

2. String X is accepted by finite automata if .
a) δ*(q,x) E A
b) δ(q,x) E A
c) δ*(Q0,x) E A
d) δ(Q0,x) E A

Explanation: If automata starts with starting state and after finite moves if reaches to final step then it called accepted.

3. Languages of a automata is
a) If it is accepted by automata
b) If it halts
c) If automata touch final state in its life time
d) All language are language of automata

Explanation: If a string accepted by automata it is called language of automata.

4. Language of finite automata is.
a) Type 0
b) Type 1
c) Type 2
d) Type 3

Explanation: According to Chomsky classification.

5. Finite automata requires minimum _______ number of stacks.
a) 1
b) 0
c) 2
d) None of the mentioned

Explanation: Finite automata doesn’t require any stack operation.

6. Number of final state require to accept Φ in minimal finite automata.
a) 1
b) 2
c) 3
d) None of the mentioned

Explanation: No final state requires.

7. Regular expression for all strings starts with ab and ends with bba is.
a) aba*b*bba
b) ab(ab)*bba
c) ab(a+b)*bba
d) All of the mentioned

Explanation: Starts with ab then any number of a or b and ends with bba.

8. How many DFA’s exits with two states over input alphabet {0,1} ?
a) 16
b) 26
c) 32
d) 64

Explanation: Number of DFA’s = 2n * n(2*n).

9. The basic limitation of finite automata is that
a) It can’t remember arbitrary large amount of information.
b) It sometimes recognize grammar that are not regular.
c) It sometimes fails to recognize regular grammar.
d) All of the mentioned