1

Answer all the questions

1. Which of the following can be considered as a first electronic computer?

(1) EDVAC (2) ENIAC (3) Atanasoff-Berry Computer (ABC)

(4) UNIVAC (5) Analytical Engine

2. Consider the following statements.

A – Data is a basic rawfacts.

B – The value of information decreases with time.

C – Information is the significant of data.

Which of the above is/are correct regarding data and information?

(1) A only (2) B only (3) C only (4) A, B only (5) A, B, C all

3. In central processing unit, “control unit uses …………….. to find next instruction for the execution”.

Which of the following is most appropriate to fill the blank in the above statement?

(1) Program Counter (2) Arithmetic Logic Unit

(3) Main memory (4) Cache memory

(5) Input device

4. Consider the following statements about Von Neumann architecture.

A- Contains central processing unit.

B- Contains main memory system.

C- Contains input-output systems.

Which of the above is /are correct?

(1) A only (2) B only (3) C only (4) A, B only (5) A, B, C all

5. The simplified result of the Boolean expression ).(.)(),( yxyxyxf is.

(1) 0 (2) 1 (3) y (4) x (5) yx .

6. Binary equivalent of 4210 is.

(1) 110101 (2) 101010 (3) 101011 (4) 111100 (5) 111110

7. The output of the Boolean function 𝑓(𝑥, 𝑦, 𝑧) = 𝑥. 𝑦 + 𝑧. 𝑥 + 𝑦. 𝑧 is 0, when.

(1) 𝑥 = 1, 𝑦 = 1, 𝑧 = 0 (2) 𝑥 = 1, 𝑦 = 0, 𝑧 = 1 (3) 𝑥 = 1, 𝑦 = 1, 𝑧 = 1

(4) 𝑥 = 0, 𝑦 = 1, 𝑧 = 1 (5) 𝑥 = 0, 𝑦 = 1, 𝑧 = 0

G.C.E. (A/L) Examination – July 2015

Conducted by Field Work Center, Thondaimanaru.

In Collaboration with the Zonal Education Office, Jaffna

Information & Communication Technology (ICT)

Grade - 12 (A/L) 2016 Part - I Time : 3 Hours

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8. In data communication, CDMA stands for.

(1) Code Division Memory Access (2) Computer Division Memory Access

(3) Code Division Multiple Access (4) Computer Division Multiple Access

(5) Communication Multiple Access

9. When the statement print ("42"+3) is executed, the result would be.

(1) 423 (2) 42 (3) 45 (4) False (5) Compile-time error

10. Which of the following is the fastest data access?

(1) Floppy disk (2) Register (3) Cache memory

(4) Harddisk (5) Random Access Memory

11. CD16 + 4B16 =

(1) 45A16 (2) 4AB16 (3) 47516 (4) 2DA16 (5) 11816

12. In which of the following phase of a system development life cycle, user requirements are included after the

system implementation?

(1) system design (2) system testing

(3) system implementation (4) system maintenance

(5) coding

13. Consider the following statements regarding e-commerce.

A - Paypal is an e-commerce business allowing money transactions through the Internet.

B - A person obtaining of air ticket from his / her house is an example for B2E e-commerce.

C - SET (secure electronic transaction) protocol is used to protect e-money transaction system in the

Internet.

Which of the above is /are correct?

(1) A only (2) B only (3) C only (4) A,C only (5) A,B,C all

14. Consider the following systems.

A – radio B – washing machine

C – blood circulatory system of human D – school

Which of the above is /are open system(s)?

(1) A only (2) B only (3) B, C only (4) A,C only (5) A,B,D only

15. Consider the following statements about data flow diagram (DFD)?

A - It represents the process model.

B - Two data stores can be directly interconnected.

C - Bothe the external entity and process can be directly interconnected.

Which of the above is /are correct?

(1) A only (2) A, B only (3) A, C only (4) B, C only (5) A, B, C all

16. Which of the following is correct regarding relational database?

(1) A table must have a primary key.

(2) Each attribute of a table should have values in the same domain.

(3) A table must have only one candidate key.

(4) A table should not contain null value.

(5) A database must have only one table.

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17. What is the output of the following python program?

a = [ 1 , 2 , 3 , None , () , [] ]

print (len(a))

(1) 3 (2) 4 (3) 5 (4) 6 (5) False

18. The following shows the descriptions for the relationships used in relational database.

(1) A is a one-to-many relationship. (2) C is a one-to-many relationship.

(3) B is a one-to-one relationship. (4) B is a many-to-many relationship.

(5) C is a many-to-many relationship.

19. Consider the following statements.

A – Guaranteed for money security.

B – Guaranteed for product quality.

C – e-commerce website is always open for customers.

Which of the above is/are correct regarding data and information?

(1) A only (2) B only (3) A, B only (4) B, C only (5) A, B, C all

20. Which of the following is a non-functional requirement of a coins booth telephone system?

(1) It should provide twenty four hours service.

(2) It should have the facility to talk more with less cost.

(3) It should have the facility to insert coins.

(4) It should have the facility to make telephone conversation.

(5) It should have the facility to enter telephone numbers.

21. One’s complement of (2310) and (-610) are respectively.

(1) 11111001 and 00000110 (2) 00010111 and 11111001 (3) 00010111 and 11111010

(4) 11111001 and 00000111 (5) 11101001 and 00000011

22. Which of the following is a valid identifier for variables?

(1) 𝑎_𝑏 (2) 𝑎#𝑏 (3) 5𝑏 (4) 𝑎 − 𝑏 (5) 𝑖𝑓

23. What is the output of the following python statement?

a = “Python”

print(a[:3])

(1) hon (2) on (3) pyth (4) pyt (5) h

25. “……………………software process model is based on risk driven and iterative fashion”.

(1) Spiral model (2) Incremental development model

(3) Waterfall model (4) Object-oriented model

(5) Rapid Application Development

A B C

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26. What is the output of the following python program?

x = 10

while x:

x = x - 1

if x % 2! = 0: continue

print (x, end=' ')

(1) 8 (2) 0 (3) 8 0 (4) 8 6 4 2 0 (5) 9 7 5 3 1

27. What is the output of the following python program?

x = 4.5

y = 2

print (x // y)

(1) 2.25 (2) 3.0 (3) 2.0 (4) 2 (5) 3

28. In operating system, “ ………………. is a function to store the state of a process and restore it”.

Which of the following is most appropriate to fill the blank in the above statement?

(1) Memory allocation (2) Context switch

(3) Programming (4) Scheduling

(5) Swapping

29. The part which is used to execute the instructions fetched into central processing unit, is called.

(1) Control unit (2) Arithmetic Logic Unit (ALU)

(3) Program counter (4) Register unit

(5) Main memory

30. Which of the following is not a stage of fetch-decode-execute cycle?

A – Control unit fetches next program instructions from memory.

B – Instructions are decoded in order to understand them by arithmetic logic unit.

C – Arithmetic logic unit executes the instructions.

(1) A only (2) A,B only (3) A,C only (4) B,C only (5) A,B,C all

31. How many bits are needed to address a byte addressable memory 4M x 16?

(1) 26 bits (2) 32 bits (3) 16 bits (4) 23 bits (5) 20 bits

32. Which of the following cannot be considered as database management system software?

(1) Linux (2) Oracle (3) MySQL (4) PostqreSQL (5) Ms-Access

33. Consider the following python statements.

A – a,b =1 B – a =1,2 C – a += 2 D – [a,b] = [1,2]

Which of the above is /are correct?

(1) A only (2) B only (3) C only (4) A,C,D only (5) A, B, C only

34. Electronic hand dryer is best described as a/an.

(1) Transaction processing system (2) Expert system

(3) Automated system (4) Agent system

(5) Artificial intelligence system

35. The system which allows only one process execution at a time, is called.

(1) Uni-programming system (2) Uni-processing system (3) Multi-programming system

(4) Multi-processing system (5) None of the above

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36. It is expected to enter all the personal and academic details of students compulsorily when students register

for university through website.

Which of the following data validation method is most suitable for this scenario?

(1) Presence check (2) Range check (3) Format check

(4) Numeric check (5) Type check

37. Consider the following logic circuit.

38. Consider the following portion of ER diagram.

Consider the followings.

A - PhoneNo is a multi-valued attribute. B - Age is a derived attribute.

C - Name is a composite attribute. D - Supervision is a unary relationship.

Which of the above is /are correct?

(1) A only (2) B only (3) A, C only (4) A,B,C only (5) A,B,C,D all

39. Which of the following python program is syntactically correct?

40. The set of rules governing the communication, is called.

(1) Protocol (2) Standard (3) Internet (4) Network (5) Medium

*****

R

What is the result of R?

(1) �̅�. �̅� + 𝐴. 𝐵

(2) 𝐴 + 𝐵̅̅ ̅̅ ̅̅ ̅̅ + 𝐴�̅�

(3) 𝐴 + �̅�

(4) �̅�𝐵 + 𝐴

(5) �̅�𝐵 + 𝐵

Supervision

Employee

EmpId

Name DateOfBirth

FirstName LastName

PhoneNo

Age

(1) if a > b

print a

else:

print b

(2) if a > b

print a

else

print b

(3) if a > b:

print a

else:

print b

(4) if a > b:

print a

else:

print b

(5) if a > b:

print a

else

print b

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Part – II A Structured Questions

Answer all the questions

01.

(a) Write down 2110 and (-710) in one’s complement 8-bits method. Show your calculations.

(b) Use one’s complement 8-bits method to add numbers 2110 and (-710). Show your calculations.

(c) Use two’s complement 8-bits method to add numbers 2110 and (-710). Show your calculations.

(d) In data communication, explain simplex mode and half-duplex mode communications with the help of

examples.

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02. Consider the following scenario.

A school library provides book lending facility for their students. Details about books, students and

borrowing details are stored in a relational database. Each student can borrow more than one books and a

book can be borrowed by more than one students in different time. The details about books such as bookId,

title and author and the details about students such as memberId, student name and address are stored. The

details such as borrowed date and returned date are also stored.

(a) Identify the entities to draw E-R diagram.

(b) Draw an E-R diagram for this scenario.

(c) Write down the possible data tables in the form of schema if the above (ii) drawn E-R diagram is mapped

into tables.

03.

(a) Write down the names of the phases of System Development Life Cycle (SDLC) for each of the following

descriptions.

Description The phase of SDLC

(i)

Developing programs.

(ii)

Comparing the actual outcome with the expected result in test

plan.

(iii)

Identifying problems in the current system.

(iv)

Using interviews, questionnaire and observation to capture

information about how to work the current system.

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(b) Explain each of the followings e-commerce models by using examples.

e-commerce

models

Explanation / Example

(i)

B2B

(ii)

B2C

(iii)

G2C

(iv)

B2E

(c) Consider the following scenario.

A clerk of a library registers for members. In some circumstances, he /she will cancel the registration.

Membership details are stored in a member file. A member may cancel his / her membership in any time.

Complete the above mentioned partial data flow diagram by identifying the missing elements. Write your

answers below.

(i) …………………………… (ii) ………………………… (iii) ………………………………

(iv) …………………………. (v) …………………………

Deposit

amount

details

(iv)

Member

details

Cancellation

request

(v)

Deposit

Register a

member

M1

M2

1 (i)

2

(iii)

(ii)

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04.

(a) Draw a flowchart to display the smallest number among three numbers entered by the user.

(b) Write down python program to display the smallest number among three numbers entered by the user.

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(c) Consider the following ER diagram.

(i) Write down the types of the following attributes.

EmpNo …………………………. EmpName ………………………….

ProName …………………………. Hours ………………………….

(ii) Explain about the “Works” relationship when the above given ER diagram is mapped into tables.

****

EmpNo Hours ProjNo

ProName

EmpName

Employee Project Works M N

FName LName

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Part II – B Essay Questions Answer any three questions only

01. A systems designer has developed a system to control street lights. The street lights can be turned on

manually, or by the use of a timer, so long as a light sensing unit indicates that it is dark.

The street light can be switched on manually or will automatically be switched on when the timer is on and the

sensor indicates the environment is dark.

This control system is required to operate the street light efficiently with the following conditions /

functionalities.

The street light can manually be switched on or off.

The timer will be either on or off.

The light sensor will detect whether the environment is light or dark.

Conditions / functionalities Boolean values

Street light switch on manually 1

Street light switch off manually 0

Timer is on 1

Timer is off 0

Sensor detects light 1

Sensor detects dark 0

(a) Obtain the Boolean expression to implement the above logic given.

(b) Construct a truth table to represent the above Boolean expression obtained in (a).

(c) Draw a logic circuit for the above Boolean expression obtained in (a) by using only AND, OR and NOT

gates.

(d) By using truth table or any other method, obtain a Boolean expression without simplification, in the form of

sum of product (SOP)

02.

(a) Briefly explain syntax errors and logical errors occurred in computer programming with the help of example.

(b) Explain what is done by the python interpreter when executing the following python program.

total = 0

while True:

s = input(‘Enter number (or “done”):’ )

if s == ‘done’: break

num = int(s)

total = total + num

print (total)

(b) Draw a flowchart to obtain total and average of ten numbers entered by user.

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03. Consider the following scenario.

The bank is organized into branches. Each branch is located in a particular city and is identified by a unique

name. Bank customers are identified by their customerid values. The bank stores each customer’s name, and

address. Customers may have accounts and can take out loans. A customer may be associated with a particular

banker, who may act as a loan officer or personal banker for that customer. Bank employees are identified by

their employeeid values. The bank administration stores the Employee’s name. Accounts can be held by more

than one customer, and a customer can have more than one account. Each account is assigned a unique account

number. The bank maintains a record of each account’s balance, and the most recent date on which the account

was accessed by each customer holding the account. A loan originates at a particular branch and can be held by

one or more customers. A loan is identified by a unique loan number. For each loan, the bank keeps track of the

loan amount.

Construct a single ER diagram for the above mentioned scenario and identify attributes and associate them with

entity or relationship types and mark primary key attributes for each entities. State any assumptions necessary to

support your design.

04.

“CarCare” is a popular car repairing service station in Sri Lanka. Hundreds of different categorized cars are

coming for repairing service in a day. 150 employees are working 24 hours in shift basis. Small scale repairing

services are immediately done. For large scale or congested time repairing services, vehicles are taken into

custody and customers are sent. After finishing repair services, customers are informed by telephone. Vehicles

are taken for repairing services on “first in first service” basis. Taking vehicles, service charges for repairing

services, working hours for employees, and their salary calculations are all done manually. The organization

realized the large amount of delay in repairing service and customer frustration. At the same time, employees

made complaint to the organization regarding delay and errors in salary payments. Therefore, the top

management of the organization proposes the computer-based solutions for these problems.

(a) Write down three disadvantages that “CarCare” would face by using this manual system.

(b)Write down three benefits that this organization would get by using computerized system.

(c) What is functional requirement of a system? State three functional requirements of this new computerized

system.

(d) Organization plans to provide insurance services for their employees through their website. What is the type

of e-commerce model most appropriate for this?

****

[End