# CBSE NET Computer-Science September-2013 Solved Paper III

1. Which of the following is a correct predicate logic statement for “Every Natural number has one successor”

1. ∀x∃y (succ (x, y) ∧ (∃z succ (x, z) ⇒ equal (y, z) ) )

2. ∀x∃y (succ (x, y) ∨ (∃z succ (x, z) ⇒ equal (y, z) ) )

3. ∃y∀x (succ (x, y) ∧ (∃z succ (x, z) ⇒ equal (y, z) ) )

4. ∀x∃ysucc (x, y)

2. α – β cutoffs are applied to ______

1. Depth first search

2. Best first search

3. Minimax search

4. Breadth first search

3. Assume that each alphabet can have a value between 0 to 9 in a CROSS + ROADS cryptoarithmetic problem____DANGER--------. Which of the following statement is true?

1. No two alphabets can have the same numeric value.

2. Any two alphabets may have the same numeric value.

3. D = 0

4. D = 1

1. 1 and 3

2. 1 and 4

3. 2 and 3

4. 2 and 4

4. Which of the following is not a part of an expert system shell?

1. Knowledge Base

2. Inference Engine

3. Explanation Facility

4. None of the above

5. The Blocks World Problem in Artificial Intelligence is normally discussed to explain a _______

1. Search technique

2. Planning system

3. Constraint satfaction system

4. Knowledge base system

6. Means-Ends Analysis process centres on the detection of difference between the current state and the goal state. Once such a difference is found, and then to reduce the difference one applies ______

1. A forward search that can reduce the difference.

2. A backward search that can reduce the difference.

3. A bidirectional search that can reduce the difference.

4. An operator that can reduce the difference.

7. Suppose a file of 10, 000 characters is to be sent over a line at 2400 bps. Assume that the data is sent in frames. Each frame consists of 1000 characters and an overhead of 48 bits per frame. Using synchronous transmission, the total overhead time is ______.

1. 0.05 second

2. 0.1 second

3. 0.2 second

4. 2.0 second

8. Which of the following is the size of Network bits and Host bits of Class Aof IP address?

1. Network bits 7, Host bits 24

2. Network bits 14, Host bits 16

3. Network bits 15, Host bits 16

4. Network bits 16, Host bits 16

9. Which of the following field of the TCP header tells how many bytes may be sent starting at the byte acknowledged?

1. TCP header length

2. Window size

3. Acknowledgement number

4. Urgent pointer

10. Which of the following is a bit rate of an 8-PSK signal having 2500 Hz bandwidth?

1. 2500 bps

2. 5000 bps

3. 7500 bps

4. 20000 bps

11. Match the following:

 List-I List-II UDP OSPF SMTP HDLC Message Transfer Protocol Bit-oriented Protocol Interior Gateway Routing Protocol ConnectionlessTransport Protocol
• A
• B
• C
• D
• 3
• 4
• 2
• 1
• 4
• 3
• 2
• 1
• 4
• 3
• 1
• 2
• 3
• 4
• 1
• 2

12. Given the IP address 201.14. 78.65 and the subnet mask 255.255. 255.224. What is the subnet address?

1. 201.14. 78.32

2. 201.14. 78.64

3. 201.14. 78.65

4. 201.14. 78.224

13. If an artificial variable is present in the ‘basic variable’ of optimal simplex table then the solution is ______

1. Alternative solution

2. Infeasible solution

3. Unbounded solution

4. Degenerate solution

14. An optimal assignment requires that the minimum number of horizontal and vertical lines that can be drawn to cover all zeros be equal to the number of

1. Rows or columns

2. Rows + columns

3. Rows + columns – 1

4. Rows + columns + 1

15. Which of the following is the minimum cost for an assignment problem given below? Jobs A B C D Workers I 5 3 2 8 II 7 9 2 6 III 6 4 5 7 IV 5 7 7 8

1. 13

2. 16

3. 17

4. 18

16. Assume, L is regular language. Let statements S1 and S2 are defined as: S1: SQRT (L) = {x| for some y with |y| = |x|2, xy∈L}. S2: LOG (L) = {x| for some y with |y| = 2|x|, xy∈ L}. Which of the following is true?

1. S1 is correct and S2 is not correct.

2. Both S1 and S2 are correct.

3. Both S1 and S2 are not correct.

4. S1 is not correct and S2 is correct.

17. A regular grammar for the language L = {anbm | n is even and m is even} is given by

1. S→aSb | S1; S1 → bS1a | λ

2. S→aaS | S1; S1 → bSb | λ

3. S→aSb | S1; S1 → S1ab | λ

4. S→aaS | S1; S1 → bbS1 | λ

18. Given the following productions of a grammar: S→ aA| aBB; A→aaA |λ B→ bB| bbC; C→ B Which of the following is true?

1. The language corresponding to the given grammar is a set of even number of a's.

2. The language corresponding to the given grammar is a set of odd number of a's.

3. The language corresponding to the given grammar is a set of even number of a's followed by odd number of b's.

4. The language corresponding to the given grammar is a set of odd number ofa's followed by even number of b's.

19. The language accepted by the nondeterministic pushdown automaton M = ({q0, q1, q2}, {a, b}, {a, b, z}, δ q0, z, {q2}) with transitions δ (q0 a, z) = { (q1 a) (q2 λ), }; δ (q1, b, a) = { (q1, b) } δ (q1, b, b) = { (q1 b) }, δ (q1, a, b) = { (q2, λ) } is

1. L (abb * a)

2. {a} U L (abb * a)

3. L (ab * a)

4. {a} U L (ab * a)

20. The language L = {an bn am bm | n ≥ 0, m ≥ 0} is

1. Context free but not linear

2. Context free and linear

3. Not Context free and not linear

4. Not Context free but linear

21. 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?

1. S1 is correct and S2 is not correct.

2. Both S1 and S2 are correct.

3. Both S1 and S2 are not correct.

4. S1 is not correct and S2 is correct.

22. Non-deterministic pushdown automaton that accepts the language generated by the grammar: S→aSS | ab is

1. δ (q0, λ z) = { (q1, z) }; δ (q0, a, S) = { (q1, SS) (q1, B), } δ (q0, b, B) = { (q1, λ) }, δ (q1, λ z) = { (qf, λ) }

2. δ (q0, λ z) = { (q1, Sz) }; δ (q0, a, S) = { (q1, SS) (q1, B), } δ (q0, b, B) = { (q1, λ) }, δ (q1, λ z) = { (qf, λ) }

3. δ (q0, λ z) = { (q1, Sz) }; δ (q0, a, S) = { (q1, S) (q1, B), } δ (q0, b, λ) = { (q1, B) }, δ (q1, λ z) = { (qf, λ) }

4. δ (q0, λ z) = { (q1, z) }

δ (q0, a, S) = { (q1, SS) (q1, B), }

δ (q0, b, λ) = { (q1, B) }.

δ (q1, λ z) = { (qf, λ) }

23. Match the following:

 List-I List-II Dangling pointer Page fault List representation Toss immediate Buffer replacement policy Variable length records Object identifier Pointer-swizzling
• A
• B
• C
• D
• 3
• 4
• 2
• 1
• 4
• 3
• 2
• 1
• 4
• 3
• 1
• 2
• 3
• 4
• 1
• 2

24. _______ constraints ensure that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation.

1. Logical Integrity

2. Referential Integrity

3. Domain Integrity

4. Data Integrity

25. The SQL expression Select distinct T, branch_name from branch T, branch S where T. Assets>S. Assets and S. Branch_city = “Mumbai” finds the names of

1. All branches that have greater assets than some branch located in Mumbai.

2. All branches that have greater assets than all branches in Mumbai.

3. The branch that has greatest asset in Mumbai.

4. Any branch that has greater assets than any branch in Mumbai.

26. Let A be the set of comfortable houses given as A = {x1/0.8, x2/0.9, x3/0.1, x4/0.7} and B be the set of affordable houses B = {x1/0.9, x2/0.8, x3/0.6, x4/0.2} Then the set of comfortable and affordable houses is

1. {x1/0.8, x2/0.8, x3/0.1, x4/0.2}

2. {x1/0.9, x2/0.9, x3/0.6, x4/0.7}

3. {x1/0.8, x2/0.8, x3/0.6, x4/0.7}

4. {x1/0.7, x2/0.7, x3/0.7, x4/0.9}

27. Support of a fuzzy set A = { x1/0.2, x2/0.15, x3/0.9, x4/0.95, x5/0.15} within a universal set X is given as

1. {x1/0.15, x2/0.15, x3/0.15, x4/0.15, x5/0.15}

2. {x1/0.95, x2/0.95, x3/0.95, x4/0.95, x5/0.95}

3. {x3, x4}

4. {x1, x2, x3, x4, x5}

28. In a single perceptron, the updation rule of weight vector is given by

1. W (n + 1) = w (n) + η[d (n) -y (n) ]

2. W (n + 1) = w (n) –η[d (n) -y (n) ]

3. w (n + 1) = w (n) + η[d (n) -y (n) ] * x (n)

4. w (n + 1) = w (n) –η[d (n) -y (n) ] * x (n)

29. ______ refers to the discrepancy among a computed, observed or measured value and the true specified or theoretically correct values.

1. Fault

2. Failure

3. Defect

4. Error

30. Which logic family dissipates the minimum power?

1. DTL

2. TTL

3. ECL

4. CMOS

31. Which of the following electronic component is not found in IC's?

1. Diode

2. Resistor

3. Transistor

4. Inductor

32. A given memory chip has 14 address pins and 8 data pins. It has the following number of locations.

1. 28

2. 214

3. 26

4. 212

33. The instruction: MOV CL, [BX] [DI] + 8 represent the _____ addressing mode.

1. Based Relative

2. Based Indexed

3. Indexed Relative

4. Register Indexed

34. The power dissipation of a flip-flop is 3mW. The power dissipation of a digital system with 4 flip-flops is given by

1. 34 mW

2. 43 mW

3. 4/3 mW

4. 12 mW

35. An astable multivibrator using the 555 timer to generate a square wave of 5 KHz with 70% duty cycle will have

1. RA = 40.4 KΩ RB = 17.25 KΩ C = 2000 pF

2. RA = 17.25 KΩ RB = 40.4 KΩ C = 2000 pF

3. RA = 40.4 KΩ RB = 17.25 KΩ C = 5000 pF

4. RA = 17.25 KΩ RB = 40.4 KΩ C = 5000 pF

36. A binary ripple counter is requred to count up to 16383. How many flip-flops are required?

1. 16382

2. 8191

3. 512

4. 14

37. The time complexity of recurrence relation T (n) = T (n/3) + T (2n/3) + O (n) is

1. O (Ig n)

2. O (n)

3. O (n Ig n)

4. O (n2)

38. How many people must there be in a room before there is a 50% chance that two of them were born on the same day of the year?

1. At least 23

2. At least 183

3. At least 366

4. At least 730

39. The number of possible parenthesizations of a sequence of n matrices is

1. O (n)

2. θ (n Ig n)

3. Ω (2n)

4. None of the above

40. The time complexity of an efficient algorithm to find the longest monotonically increasing subsequence of n numbers is

1. O (n)

2. O (n Ig n)

3. O (n2)

4. None of the above

41. Given a binary search trees for a set of n = 5 keys with the following probabilities: i 0 1 2 3 4 5 pi – 0.15 0.10 0.05 0.10 0.20 qi 0.05 0.10 0.05 0.05 0.05 0.10 The expected optimal cost of the search is

1. 2.65

2. 2.70

3. 2.75

4. 2.80

42. Given 0 − 1 knapsack problem and fractional knapsack problem and the following statements: S1: 0 − 1 knapsack is efficiently solved using Greedy algorithm. S2: Fractional knapsack is efficiently solved using Dynamic programming. Which of the following is true?

1. S1 is correct and S2 is not correct.

2. Both S1 and S2 are correct.

3. Both S1 and S2 are not correct.

4. S1 is not correct and S2 is correct.

43. Equivalence class partitioning approach is used to divide the input domain into a set of equivalence classes, so that if a program works correctly for a value, then it will work correctly for all the other values in that class. This is used _____.

1. To partition the program in the form of classes.

2. To reduce the number of test cases required.

3. For designing test cases in white box testing.

4. all of the above:

44. The failure intensity for a basic model as a function of failures experienced is given as λ (μ) -λ0[1 – (μ)/(V0) ] where λ0 is the initial failure intensity at the start of the execution, μ is the average or expected number of failures at a given point in time, the quantity V0 is the total number of failures that would occur in infinite time. Assume that a program will experience 100 failures in infinite time; the initial failure intensity was 10 failures/CPU hr. Then the decrement of failures intensity per failure will be

1. 10 per CPU hr.

2. 0.1 per CPU hr.

3. –0.1 per CPU hr.

4. 90 per CPU hr.

45. Improving processing efficiency or performance or restructuring of software to improve changeability is known as

1. Corrective maintenance

2. Perfective maintenance

4. Code maintenance

46. In ____, modules A and B make use of a common data type, but perhaps perform different operations on it.

1. Data coupling

2. Stamp coupling

3. Control coupling

4. Content coupling

47. Consider the following schemas: Branch_Schema = (branch_name, assets, city) Customer_Schema = (cutstomer_name, street, city) Deposit_Schema = (branch_name, account_number, customer_name, balance) Borrow_Schema = (branch_name, loan_number, customer_name, amount) This of the following tuple relational calculus finds all customers who have loan amount more than Rs. 12, 000?

1. {t (customer_name) | t∈borrow[? ] t[amount]>12000}

2. {t |t (customer_name) | t∈borrow[? ] t[amount]>12000}

3. {t |[? ] ∈ borrow (t (customer_name = s (customer_ name) ) ) [? ] [Amount]>12000}

4. {t |[? ] ∈ borrow (t (customer_name) ) [? ] s[amount] >12000}

48. Match the following

 List-I List-II Create Select Rectangle Record The E-R Model Relationship Model DDL DML
• A
• B
• C
• D
• 3
• 4
• 1
• 2
• 4
• 3
• 2
• 1
• 4
• 3
• 1
• 2
• 3
• 4
• 2
• 1

49. Sixty (60) reusable components were available for an application. If only 70% of these components can be used, rest 30% would have to be developed from scratch. If average component is 100 LOC and cost of each LOC is Rs. 14, what will be the risk exposure if risk probability is 80%?

1. Rs. 25, 200

2. Rs. 20, 160

3. Rs. 25, 160

4. Rs. 20, 400

50. Consider the following two function declarations:

1. int * f ()

2. int ( * f) ()

Which of the following is true?

1. Both are identical.

2. The first is a correct declaration and the second is wrong.

3. Both are different ways of declaring pointer to a function.

4. The first declaration is a function returning a pointer to an integer and the second is a pointer to function returning integer.

51. Assume that we have constructor function for both Base and Derived classes. Now consider the declaration: Main () Base * p = new Derived; In what sequence, the constructor will be executed?

1. Derived class constructor is followed by Base class constructor.

2. Base class constructor is followed by Derived class constructor.

3. Base class constructor is never called.

4. Derived class constructor is never called.

52. What is the output of the following program? #include<stdio. h> main () { int a, b = 0; static int c[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 0}; for (a = 0; a<10; + + a); if ( (c[a]%2) = = 0) b + = c[a]; printf ( “%d” b); }

1. 15

2. 25

3. 45

4. 20

53. A Program contains the following declarations and initial assignments int i = 8, j = 5; double x = 0.005, y = –0.01; char c = ‘c’ d = ‘d’ Determine the value of the following expressions which involve the use of library functions: Abs (i − 2 * j); log (exp (x) ); toupper4

1. 2; 0.005; D

2. 1; 0.005; D

3. 2; 0.005; E

4. 1; 0.005; e

54. MPEG involves both spatial compression and temporal compression. The spatial compression is similar to JPEG and temporal compression removes ______ frames.

1. Temporal

2. Voice

3. Spatial

4. Redundant

55. If the data unit is 111111 and the divisor is 1010. In CRC method, what is the dividend at the transmission before division?

1. 1111110000

2. 1111111010

3. 111111000

4. 111111

56. If user A wants to send an encrypted message to user B. The plain text of A is encrypted with the _______.

1. Public Key of user A

2. Public Key of user B

3. Private Key of user A

4. Private Key of user B

57. A _____ can forward or block packets based on the information in the network layer and transport layer header.

1. Proxy firewall

2. Firewall

3. Packet filter firewall

4. Message digests firewall

58. Which of the following graphics devices are known as active graphics devices?

1. Alphanumeric devices

2. Thumb wheels

3. Digitizers

4. Joystics

1. 1 and 2

2. 3 and 4

3. 1, 2 and 3

4. 1, 2, 3 and 4

59. A diametric projection is said to be trimetric projection when

1. Two of the three foreshortening factors are equal and third is arbitrary.

2. All of the three foreshortenng factors are equal.

3. All of the three foreshortening factors are arbitrary.

Which of the above is true?

1. 1 and 2

2. 2 and 3

3. 1 only

4. 3 only

60. Which of the following is/are fundamental method (s) of antialiasing?

1. Increase of sample rate.

2. Treating a pixel as a finite area rather than as a point.

3. Decrease of sample rate.

1. 1 and 2

2. 2 and 3

3. 1 only

4. 2 only

61. The two color systems – the HSV and HLS are

1. Hue, Saturation, Value and Hue, Lightness, Saturation.

2. High, Standard, Value and High, Lightness, Saturation.

3. Highly, Saturated, Value and Highly, Lightened, Saturation.

4. Highly, Standard, Value and Hue, Lightness, Saturation.

62. The parametric representation of the line segment between the position vectors P1 (2, 3) and P2 (5, 4) is given as

1. x (t) = 2 + 7t, y (t) = 3 + 7t 0 ≤ t ≤ ∝

2. x (t) = 2 + 10t, y (t) = 3 + 12t 0 ≤ t ≤ 1

3. x (t) = 2 + 3t, y (t) = 3 + t 0 ≤ t ≤ 1

4. t (x, y) = 14t 0 ≤ t ≤ 1

63. Consider the following sequence of operations:

1. Pointer p1 is set to point at a new heap-dynamic variable.

2. Pointer p2 is assigned p1's value.

3. The heap dynamic variable pointed to by p1 is explicitly de-allocated, but p2 is not changed by the operation.

This situation leads to which of the following:

1. p1 becomes a dangling pointer

2. p2 becomes a dangling pointer

3. Both p1 and p2 are now dangling pointers

4. Neither p1 nor p2 is now a dangling pointer

64. The programming languages C and C + + are not strongly typed languages because:

1. Both C and C + + allow functions for which parameters are not type checked.

2. Both C and C + + allow functions for which parameters are type checked.

3. Both C and C + + allow functions for which parameters are not type checked and also the union types in these languages are not type checked.

4. Union types in these (C and C + + ) languages are not type checked.

65. The tracing model in Prolog describes program execution in terms of certain events. These events are

1. Call and exit

2. Call and fail

3. Call, exit and redo

4. Call, exit, redo and fail

66. Which of the following statements is not correct with reference to distributed systems?

1. Distributed system represents a global view of the network and considers it as a virtual uniprocessor system by controlling and managing resources across the network on all the sites.

2. Distributed system is built on bare machine, not an add-on to the existing software.

3. In a distributed system, kernel provides smallest possible set of services on which other services are built. This kernel is called microkernel. Open servers provide other services and access to shared resources.

4. In a distributed system, if a user wants to run the program on other nodes or share the resources on remote sites due to their beneficial aspects, user has to log on to that site.

67. A system contains 10 units of resource of same type. The resource requirement and current allocation of these resources for three processes P, Q and R are as follows: P Q R Maximum requirement 8 7 5 Current allocation 4 1 3 Now, consider the following resource requests:

1. P makes a request for 2 resource units.

2. Q makes request for 2 resources units.

3. R makes a request of 2 resource units.

For a safe state, which of the following options must be satisfied?

1. Only request 1

2. Only request 2

3. Only request 3

4. Request 1 and 2

68. Consider the following set of processes with the length of CPU burst time in milliseconds (ms): Process A B C D E Burst time 6 1 2 1 5 Priority 3 1 3 4 2 Assume that processes are stored in ready queue in following order: A – B – C – D – E Using round robin scheduling with time slice of 1 ms, the average turn around time is

1. 8.4 ms

2. 12.4 ms

3. 9.2 ms

4. 9.4 ms

69. Consider a main memory with 3 page frames for the following page reference string: 5, 4, 3, 2, 1, 4, 3, 5, 4, 3, 4, 1, 4 Assuming that the execution of process is initiated after loading page 5 in memory, the number of page faults in FIFO and second chance replacement respectively are

1. 8 and 9

2. 10 and 11

3. 7 and 9

4. 9 and 8

70. Which of the following shell scripts will produce the output “my first script”

1. For 1 in my first script {echo –i $i} 2. For my first script; do echo –n; done 3. For 1 in my first script; do echo –i$i; done

4. For n in my first script; do echo –i \$i; done

71. The portion of Windows 2000 operating system which is not portable is

1. Processor management

2. User interface

3. Device management

4. Virtual memory management

72. Match the following for Windows Operating System:

 List-I List-II Hardware abstraction layer Kernel Executive Win32 subsystem Starting all processes, emulation of different operating systems, security functions, transform character based applications to graphical representation. Export a virtual memory interface, support for symmetric multiprocessing administration, details of mapping memory, configuring I/O buses, setting up DMA. Thread scheduling, interrupt and exception handling, recovery after power failure. Object manager, virtual memory manager, process manager, plug and-play and power manager.
• A
• B
• C
• D
• 1
• 3
• 2
• 4
• 4
• 3
• 2
• 1
• 2
• 3
• 4
• 1
• 3
• 2
• 1
• 4