21. Which of the following data structures is most efficient in terms of both space and time to reverse a string of characters?
(A) Linked list
22. Which of the following can be the sequence of nodes examined in a binary search tree while searching for key 98?
(A) 100, 50, 75, 60, 98
(B) 100, 120, 90, 95, 98
(C) 200, 70, 100, 95, 98
(D) 75, 150, 90, 80, 98
23. Which of the following is true for a sorted list with ‘n’ elements?
(A) Insertion in a sorted array takes constant time.
(B) Insertion in a sorted linear linked list takes constant time.
(C) Searching for a key in a sorted array can be done in O(log n) time.
(D) Searching for a key in a sorted linear linked list can be done in O(log n) time.
24. Files that are related to input/output and are used to model serial I/O devices such as terminals, printers and networks are called :
(A) regular files
(B) character special files
(D) block special files
25. An example of a possible file attribute is:
(A) minimum size
(B) permanent flag
(C) archive flag
(D) EBCDIC flag
26. The ATM cells are ................ bytes long.
27. For slotted ALOHA, the maximum channel utilization is :
28. For a channel of 3 KHz bandwidth and signal to noise ratio of 30 dB, the maximum data rate is:
(A) 3000 bps
(B) 6000 bps
(C) 15000 bps
(D) 30000 bps
29. An example of a public key encryption algorithm is:
(A) Caesar cipher algorithm
(B) DES algorithm
(C) AES algorithm
(D) Knapsack algorithm
30. With reference to hierarchical routing, the optimum number of levels for an m router subnet is:
(C) ln m