Computer Science CSS Paper 2000

FEDERAL PUBLIC SERVICE COMMISSION
COMPETITIVE EXAMINATION FOR RECRUITMENT TO POSTS
IN B.P.S. – 17, UNDER THE FEDERAL GOVERNMENT, 2000
COMPUTER SCIENCE
Time Allowed: 3 Hours Maximum Marks: 100

NOTE:
1. Attempt FIVE questions in all, including Question No. 8, which is compulsory. There should be at least ONE question from each section. All questions carry equal marks.
2. Illustrate your answers with diagrams and sketches whenever necessary.
3. Answers should be neat, clean and to the point. Avoid unnecessary details but record facts and any assumptions made.

SECTION – A

1. (a) Illustrate the basic computer architecture and define the functions of its main components. [10]
   (b) Describe in detail the memory types used in computers. How data and instructions are communicated to and from the computer memory. [10]

2. (a) Define the operating system and its function. List different operating systems available in the market. [10]
   (b) Why scheduling is necessary in operating system? Briefly describe various scheduling policies. [10]

3. (a) Illustrate a simple LAN model showing major LAN components and their functions. What types of changes need to be made in such a model if the speed of data communication is to be increased? [10]
   (b) Describe ISO reference model. Explain at which layers, the TCP/IP works. [10]

SECTION – B

1. Write a simple program in C/C++ to calculate the marks of each student appearing in this paper. The marks must be identified for each section (A, B,…), question (1,2,…) and part of the question (a, b, etc.). The program must calculate the total marks obtained subject to following conditions. [20]
2. Only five questions are attempted. Student must attempt compulsory question and at least one question from each section. Marks of one question will not be counted if no question is attempted from any one section.
3. Al questions carry equal (20) marks each. All marks are equally divided in question parts (a, b, c,…etc.).
4. There is no negative marking. Student must not get more than maximum marks allotted to the question attempted.

5. (a) Describe the difference between a queue and a stack. How these are handled in a C/C++ program. Describe various situations in which you will use stack instead of queue. [10]
   (b) Briefly contrast various Software Department Life Cycle models and discuss their effectiveness in appropriate situations. [10]

SECTION – C

1. (a) Define a data model. Describe various sets of information this model provides. Critically examine, which information (with respect to program development) is not described by the data model alone. [10]
   (b) A Relational Model is commonly used database model. What are essential characteristics of the Relation Model? And why do we use nomalisation? [10]

2. (a) Briefly contrast the uses of HTML, CGI, PERL, JAVA Applets in web page design. Where and when will you prefer to use these?
   (b) What is meant by windowing and clipping operations? Describe the clipping techniques with examples. [10]

3. (A) Identify TRUE and False statements.

4. Application program instructions are loaded in the main memory just before execution. (True/False)

5. ALU performs control task. (True/False)

6. Paging operation in operating system is performed to allot page numbers to different chunks of data to be processed. (True/False)

7. The Basic difference between WAN and LAN is speed of data communication and not the size of data. (True/False)

8. Inheritance and Polymorphism are two essential properties considered in Object-Oriented Programming. (True/False)

9. Tree structure will have more paths with the large size of same data. (True/False)

10. Object-oriented Methods use data and process (on the data) defined as a single entity. (True/False)

11. E-R model also defines the minimum and maximum values in each relationship of data entities. (True/False)

12. Structured models do not use data model. (True/False)

13. Scanning is a process to convert hard copy of the computer files. (True/False)

(B) Please choose the most appropriate answer from the given set of answers to fill the blanks.

1. During the program execution, temporary/intermediate values are stored in _____________.
   a. Registers b. Peripherals c. LAN d. None of these

2. The objects can be inherited by _____________.
   a. A single object only b. Multiple objects c. Both (a) and (b) d. Either (a) or (a)

3. The operating system may perform _____________ operation to manage the memory while running a large program.
   a. Sorting b. Scheduling c. Paging d. None of these

4. When the LAN is arranged in such a way that each computer is connected directly to the HUB the configuration can be termed as _____________ network.
   a. Bus b. Star c. Ring d. None of these

5. To communicate with other computers over a telephone line the computer must have _____________ installed.
   a. Telephone set b. Modem c. LAN Card d. None of these

6. When each item of data in a database is directly linked with every other item of data, the database is called _____________.
   a. Relational b. Hierarchical c. Network d. None of these

7. _____________ is the most efficient method to reduce the duplication of data.
   a. Duplication b. Normalisation c. Empty fields d. None of these

8. The _____________ operation changes the coordinate values of objects being displayed.
   a. Transformation b. Windowing c. Both (a) and (b) d. None of these

9. A linear sequential software development model is also referred to as ____________ .
   a. Prototype Model b. RAD Model c. Spiral Model d. None of these

10. State Transition Diagram gives information of ___________.
    a. Data Flow b. Entry Relationship c. Control Flow d. None of these