UGC NET Solved Computer Science Paper III June 2014 - Part 8

71.       A network on the Internet has a subnet mask of 255.255.240.0. What is the maximum number of hosts it can handle?

(A) 1024

(B) 2048

(C) 4096

(D) 8192

Answer: C

72.       Four bits are used for packed sequence numbering in a sliding window protocol used in a computer network. What is the maximum window size?

(A) 4

(B) 8

(C) 15

(D) 16

Answer: C

73.       Given the following two grammars :

G1 : S ® AB | aaB

A ® a | Aa

B ® b

G2 : S ® a S b S | b S a S | l

Which statement is correct?

(A) G1 is unambiguous and G2 is unambiguous.

(B) G1 is unambiguous and G2 is ambiguous.

(C) G1 is ambiguous and G2 is unambiguous.

(D) G1 is ambiguous and G2 is ambiguous.

Answer: D

74.       Match the following :

List – I

a. Chomsky Normal form

b. Greibach Normal form

c. S-grammar

d. LL grammar

List – II

i. S ® b S S | a S | c

ii. S ® a S b | ab

iii. S ® AS | a

A ® SA | b

iv. S ® a B S B

B ® b

Codes :

      a    b    c   d

(A) iv   iii    i    ii

(B) iv   iii    ii   i

(C) iii   iv    i    ii

(D) iii   iv    ii   i

Answer: C

75.       Given the following two languages :

L1 = {aⁿbⁿ | n ≥ 1} È {a}

L2 = {w C w^R | w Î {a, b}*}

Which statement is correct?

(A) Both L1 and L2 are not deterministic.

(B) L1 is not deterministic and L2 is deterministic.

(C) L1 is deterministic and L2 is not deterministic.

(D) Both L1 and L2 are deterministic.

Answer: D