Time is running out ! 3 Weeks for HSST Computer Science Exam.

HSST Examination 2011 Expected Answer Key(Category No:111/2010)

Exam held on 01/09/2011

Correct Answers 
Unsure answers.

In C language an user defined header is identified by the inclusion :
(A) # include "test.h"
(B) # include < test.h >
(C) include "test.h"
(D)None of these

2. Number of locations that could be addressed by a microprocessor with 12
address lines is :
(A)1024
(B) 64K
(C) 4096
(D) 2048

3. Number of bit width of any memory chip is :
(A) 16
(B) 64
(C) 32
(D) 8

4. The command that lists the last few lines from a file name "file"
(A) tail file
(B) end file
(C) grep file
(D) cat file -last25

5. The percentage of time that a computer system is not available for use is :
(A) Down Time
(B) Seek Time
(C) Delay Time
(D) Access Time

6. By the thread of the same process, sharing is not allowed in :
(A) queue
(B) message
(C) stack
(D) address space

7. How to declare an interface class in C++ ?
(A) by declare all methods pure virtual in a class
(B) make all metods abstract in a class
(C) declare the class as interface
(D) none of the above

8. Which device translates between data formats ?
(A) Hub
(B) Switch
(C) Bridge
(D) Gateways

9. In a relation is in BCNF then it is in :
(A) 2NF
(B) 3NF
(C) 1NF
(D) 1NF and 2NF

10. Minimum Hamming distance method is used for correction of :
(A)syntactic error
(B) semantic errors
(C) algorithm errors
(D) programming errors.

11. Full Binary tree with n leaves contain
(A)n nodes
(B)2n-1 nodes
(C)n-1 nodes
(D)log n nodes

12. What is not possible in a thread?
(A)Ready
(B)Wait
(C)Suspended
(D)Running

13. The margin of a word document can be displayed on the horizontal or
vertical ruler with the mouse and the:
(A)FONT SIZE button
(B)ALT Key
(C)DELETE Key
(D)CTRL Key

14. The 2's complement of the binary value 10 is
(A)10
(B)11
(C)01
(D)110 

15. The property that OOPs will permit the same operation to be carried out
differently, based on the object
(A)inheritance
(B)polymorphism
(C)function overloading
(D)data abstraction

16. The IP address 127.0.0.1 is named as
(A)Loopback address
(B)IP address in a standard network
(C)LAN server address
(D)Default router address

r
17. The Virtual Memory is located logically:
(A) in the CPU
(B) in main Memory
(C) in between CPU and primary memory
(D) in the Hard disk

18. The Banker's algorithm in resource allocation deals with':
(A) Dead lock prevention
(B) Dead lock recovery
(C) Dead lock avoidance
(D) Mutual exclusion
Ref: P-256, Operating System Concepts,Silberschatz-Galvin-Gagne

19. Thrashing occurs in:
(A) large computers
(B) a natural consequence of the virtual memory system
(C) can always be avoided by swapping
(D) poor paging algorithm 
Ref: P-348, Operating System Concepts,Silberschatz-Galvin-Gagne

20. Compilers can identify:
(A) syntax errors
(B) semantic errors
(C) logical errors
(D) mathematical errors

21. What was the first Scientific Computer Programming Language?
(A) COBOL
(B) LISP
(C) ADA
(D)FORTRAN 
Ref: wikipedia.org/wiki/Fortran

22. Which is the first Object Oriented Language?
(A) ADA
(B) COBOL
(C) LISP
(D) FORTRAN
Really Simula is considered as the first Object Oriented Language .Ref: en.wikipedia.org/wiki/Simula

23. Producer consumer problem is example for application of:
(A) Monitors
(B) For Monitors, Semaphores and Event counters
(C) Semaphores
(D) Event counters

24. What was the data transmission method in which bi-directional data flow
is allowed?
(A) Simplex
(B) Duplex
(C) Analog
(D) Single side mode

25. Yahoo was developed by :
(A) Dennis Ritchie and Ken Thompson
(B) Vint Cerf and Robert Kahn
(C) David Filo and Jerry Yang
(D) Steve Case and Jeff Bezos
Ref: docs.yahoo.com/info/misc/history.html

26.Resolution of Video display unit does not depend on:
(A) Raster scan rate
(B) Band width
(C) Vertical and horizontal Scans
(D) Screen size

27.Resolution of Video display unit does not depend on:
(A) Raster scan rate
(B) Band width
(C) Vertical and horizontal Scans
(D) Screen size

28. The true statement for parallel transmission is :
(A) simultaneous transmission of all bits
(B) speed is specified in bps
(C) slower than serial
(D) micro computers use this

29. Gray code for the decimal number 7 is :
(A) 0111
(B) 0100
(C) 0101
(D)1011

30. Evaluate the pre-fix expression -*63-41 will result in :
(A) 25
(B) 23
(C) 15
(D) 12

3l. Error correction in the data link layer is achieved by:
(A) Equalization
(B)Cyclic redundancy codes
(C) Hamming codes
(D) Bit stuffing
Ref: Page-223, Computer Fundamentals,P.K. Sinha

.
32. The system program that set up executable program in RAM, ready for
execution is :
(A) Loader 
(B) Linker
(C) Linkage editor
(D) Compiler ,

33. File transfer protocol that uses UDP is :
(A) FTP
(B) TFTP
(C) TELNET
(D) NFS
Ref: P-505, Internet Working with TCP/IP, D. Comer

34. To check the presence of a computer in the network,use the command:
(A) ping
(B) cmd
(C) check
(D) ipconfig
Ref: P-133, Internet Working with TCP/IP, D. Comer

35. In cryptology the code STUDYING is written as RUTEXJMH, then the
code for OTHER is :
(A) TOHRE
(B) ROHTE
(C) NUGFQ
(D) MOTHR

36. The Number of the equivalent relations of the set {1,2,3,4} is :
(A) 4
(B) 15
(C) 16
(D) 24

37. Which of the sets are empty?
(A) { x : x = / x}
(B) {x:x=x}
(D) {x:x =/ xx}
(C) {x:x=/x2}

38. In any undirected graph, the sum of the degrees of all nodes is :
(A) must be even
(B) is always ODD
(C) need not be even
(D) is twice number of edges
Ref: Common sense. Twice indicate the number will even. But ‘0’ is an
exception. Then choice (c) is true.

39. An undirected graph is Eulerian if and only if all vertices of G are of the
sum of the degrees of all nodes is :
(A) Same degree
(B) ODD degree
(C) Need not be ODD
(D) Is twice number of edges

40. An undirected graph G has n vertices n - 1 edges then G is :
(A) Cyclic
(B) Addition of edge will make it cyclic
(C) Eulerian
(D) Is a Tree

41.Graph having every pair of vertices connected is called :
(A) Cycle graph
(B) Complete graph
(C) Peterson graph
(D) Is a Tree

42. The Eigen vectors of a real symmetric matrix corresponding to different
Eigen values are:
(A) Orthogonal matrix
(B) Singular matrix
(C) Non-singular matrix
(D) Inverse matrix

43. The system of equations 4x + 6y = 8, 3x + 2y = 1, 7x + 8y = 9 has:
(A) only one solution
(B) infinite solutions
(C) two solutions
(D) none of these

44. The Eigen values of the square matrix are:
(A) positive
(B) imaginary
(C) real
(D) negative

45. The Equations will have:
(A) no unique solution
(B) only one solution
(C) has only two solutions
(D) has infinite

46.Which is fastest ?
(A) DTL
(B) TTL
(C) ECL
(D) CMOS

47.Which is commutative but not associative?
(A) NOT
(B) NOR
(C) XOR
(D) NAND
Ref:http://larc.ee.nthu.edu.tw/~cww/n/228/03.pdf

48. Which is Universal gate?
(A) AND
(B) NOR
(C) XOR
(D) NOT

49. How many NAND gates are needed to perform X . Y ?
(A) 3
(B) 4
(C) 2
(D) 1

50. Which is non-volatile?
(A) RAM
(B) PROM
(C) EPROM
(D) ROM
Ref: http://en.wikipedia.org/wiki/EPROM

51. Which is the access method to take data from tape memory?
(A) Direct
(B) Sequential
(C) Parallel
(D) Serial
Ref: Page-84, Computer Fundamentals, P.K. Sinha.

52. The cycle time for a memory system is :
(A) access time
(B) longer than access time
(C) less than access time
(D) sub multiple of access time

53. How many RAM chips are needed to generate the (256K X 1 bit)?
(A) 8
(B) 12
(C) 32
(D) 64

54. T flip-flops are generally used for:
(A) counter
(B) delay switch
(C) counter and frequency divider
(D) decoder

55. Register used as working area in CPU is:
(A) Program counter
(B) Stack,
(C) Instruction register
(D) Accumulator 
Ref: http://en.wikipedia.org/wiki/Accumulator

56. A microprocessor can be :
(A) Programmable
(B) Non Programmable
(C) Micro programmable
(D) All of the above

57. Which is 16 bit microprocessor?
(A) Z 80
(B) Motorola 6800
(C) Intel 8086
(D) Intel 80486
Ref: http://en.wikipedia.org/wiki/Intel_8086

58. "n" flip-flops will divide the frequency into a factor of :
(A) n
(B) 1/n
(C) 2 to the power of' n '
(D) log(n)

59. 8 2 4 1 is the :
(A) BCD code
(B) Gray code
(C) Excess -3 code
(D) ASCII code

60. (1001000010011001) base 2; equivalent in base 16 is :
(A) 9899
(B) 9989
(C) 8999
(D) 9999

61.Which is a programmable interval timer?
(A) 8253
(B) NE 555
(C) 8275
(D) 8251
Ref: http://en.wikipedia.org/wiki/Intel_8253

62. Negative number cannot be represented in:
(A) Signed magnitude form
(B) 1's complement form
(C) 2's complement form
(D) None of the above forms

63.Which of the following interrupt is both level and edge sensitive?
(A) RST 5.5
(B) INTER
(C) TRAP
(D) RST 7.5

64. What is a BUFFER?
(A) Convert input data to output
(B) CPU stores program counter
(C) An Interphase between CPU and peripheral
(D) Convert program to EXE form

65. By default any real number in C is represented as :
(A) a float
(B) a double
(C) a long double
(D) long float

66. Integer division in "C" program results in :
(A) Truncation
(B) Rounding
(C) Overflow
(D) None of above
Ref: P-48,Programming in ANSI C, E. Balagurusamy.

67.The function sprintf() works like printf(), but operates on:
(A) data in a file
(B) stderr
(C) stdin
(D) string 
Ref:http://en.wikibooks.org/wiki/A_Little_C_Primer/The_C_sprintf_Fu
nction

68. The function exit( ) causes an exit from:
(A) from loop .
(B) from the block
(C) from the function
(D) from program 
Ref :http://www.thinkage.ca/english/gcos/expl/c/lib/exit.html

69. The complexity of linear search algorithm of an array of n elements is :
(A) 0 log(n)
(B) 0 (n)
(C) Onlog(n)
(D) O(nXn)

70. How many elements can array A (-1..m ,1..m) have?
(A) mXm
(B)(m + l)(m + 1)
(C) mX(m-1)
(D)((m - n)Xn)

71. Which is useful to implement quick sort?
(A) List
(B) Set
(C) Stack
(D) Queue

72. Recursively enumerable languages are closed under:
(A) Union
(B) Intersection
(C) Complementation
(D) Concatenation 

73. The Grammar that produce more than one Parse tree for same sentence is :
(A) Ambiguous
(B) Unambiguous
(C) Complementation
(D) Concatenation Intersection

74. The number of the external states of a Turing Machine should be at least:
(A) 1
(B) 2
(C) 3
(D) 4

75. Give name of the database in the general model of a compiler:
(A) Literal table
(B) Terminal table
(C) SYMTAB
(D) Productions

76. A file is :
(A) an abstract data type
(B) logical storage unit
(C)usually non volatile
(D) volatile

77. What property of the files prevent sharing of files and directories?
(A)Tree Structure
(B) One level.structure
(C) Two level structure
(D) Length

78. E-R modeling technique is :
(A) Tree structure
(B) Top-down method
(C) Bottom-up method
(D) Right-left approach

79. Data items stored as grouped items is :
(A) Record
(B) List
(C) Strings
(D) Title list

80. Data items are fragmented, replicated and propagated in :
(A) DBMS
(B) RDBMS
(C) DDBMS
(D) DML

8l. In data manipulation the first element of T[5] is :
(A) T[l]
(B) T[O]
(C) T[5]
(D) T[3]

82 . Processed data is called:
(A) Data base
(B) File
(C) Information
(D) Sample

83 . Which factor of coding is most important?
(A) Productivity
(B) Cost
(C) Readability
(D) Less memory usage

84. Main container for < TR > < TD > and < TH > is':
(A)< TABLE >
(B)< GROUP >
(C)< DATA >
(D)< CAPTION >

85. Which of the following is the non-polling system?
(A) Stop and wait
(B) Daisy chain
(C) DMA
(D) TDMA

86. What is the working Principle of a Digital Computer?
(A) De Morgan's Principle
(B) Len's Principle
(C) Von Neumann's Principle
(D) Euler's Principle

87. Give the unique name of the combination of Analog and Digital
Computer
(A) Cray XMP 120 Computer
(B) Param 2000 Computer
(C) IBM 320 Computer
(D) Hybrid Computer
Ref: Page-237, Computer Fundamentals, P.K. Sinha.

88. Why RAM is kept near to the Processor in a Digital Computer?
(A) Reduce the cost
(B) Get maximum speed
(C) To minimize memory access time
(D) Increase frequency

89. Who designed the First Digital computer using the Binary system?
(A) Blaise Pascal
(B) Agutha Ada
(C) Isaac Newton
(D) Dr. Sakunthala Devi

90. Give the name of the first Operating system for Personal Computers:
(A)Linux
(B)Windows 3.2
(C) CP/M 
(D) Disk Operating System

91. Which of the following preposition is a tautology?
(A) pvq->p
(B) p->(q->p)
(C) pv(q->p )
(D) None of these

92. p -> q -> r is equivalent to :
(A) p -> q -> r
(B) p ->( q -> r)
(C) pv(q-> r)
(D) None of These

93. Why do we go for Normalization of Data Bases?
(A) To avoid the repetitions
(B) To prevent fragmentation
(C) Avoid redundancy
(D) To prevent replication

94. Name the component carrying the ALU and Control Unit in Digital
Computer:
(A) Microprocessors
(B) Nano chips
(C) MEMS
(D) Hybrid Computer 

95. Give the name of the Linear list in which elements can be added at ends
but not in the /middle:
(A) Array
(B) Queue 
(C) Tree
(D) Circular Queue

96.The switching sed in First generation computer were :
(A) Transistors
(B) SSI chips
(C) VLSI Ghips
(D) Vacuum Tubes

97. The automaton accepting the regular expression of any number of a's is :
(A) a* 
(B)ab*
(C) (a/b)*
(D)a*b*c*

98.Flip-flop is the basic structure of the device
(A) Hard disk
(B) Memory
(C) Cells
(D) Speakers

99. In C language data type of "3" is :
(A) an integer
(B) a word
(C) a character
(D) a digit

100. If every node "a" in a graph G is adjacent to every node "b" in G, then
the graph is ;
(A) Isolated graph
(B) Connected graph 
(C) Eulerian graph
(D) Complete graph