year 11 computing marking scheme...pen drive magnetic file allocation table hierarchical sector...

Computing – Marking Scheme – Year 11 – 2019 of 12

DEPARTMENT FOR CURRICULUM,

LIFELONG LEARNING AND EMPLOYABILITY

Directorate for Learning and Assessment Programmes

Educational Assessment Unit

Annual Examinations for Secondary Schools 2019

YEAR 11 COMPUTING MARKING SCHEME

Directions to candidates:

Answer ALL questions in Section A and Section B on this paper.

The use of a flow chart template is permitted.

Calculators are NOT allowed.

Good English and orderly presentation are important.

For office use only:

QUES 1 2 3 4 5 6 7 8 9 10 11 12 13 Paper

Total

Course

Work

Final

Mark

MAX 5 5 5 5 5 5 5 5 5 5 5 15 15 85% 15% 100%

MARK

MARKING SCHEME

of 12 Computing – Marking Scheme – Year 11 – 2019

Section A

1. Input devices are used to enter data into digital devices. Output devices receive the processed data and produce useful information.

For each of the following statements state if it is true or false.

The Magnetic-Ink reader is suitable for POS systems: False [1]

The Plotter produces raster images: False [1]

Some peripherals can be both input and output devices: True [1]

An Optical Mark Reader is suitable for correcting

multiple-choice exam questions: True [1]

Input/output buffering helps to improve the overall system

performance when input and output devices are used: True [1]

2. Secondary storage devices, such as hard disks and pen drives, are

non-volatile storage devices that enable permanent data storage. Using the terms below, fill in each statement appropriately.

Pen drive Magnetic File Allocation Table Hierarchical Sector

Tapes use this kind of technology to store data

onto them: Magnetic [1]

Many operating systems use this kind of filing

system to view the drives, folders and files: Hierarchical [1]

This is the minimum storage unit of a hard drive: Sector [1]

A device which uses electronic technology: Pen drive [1]

This is used by the operating system to manage

files on hard drives: File Allocation Table [1]

3. Language translators are computer programs that translate a program, written in a programming language, into machine language that can be processed by the CPU. For each statement below write the appropriate

term.

This translator is used for low-level languages: Assembler [1]

A program (code) as written by a programmer: Source code [1]

A translator which scans the entire program, translates it and produces an executable code: Compiler [1]

Mnemonics such as ADD and DIV are used by this

language: Assembly language [1]

This translator is best used during program

development: Interpreter [1]


4. In the computing industry, for example gaming companies, an effective

end-product is the result of teamwork. Typically, various types of professionals ranging from system analysts to programmers and testers

work together.

Answer the questions that follow:

a. i. The Systems Analyst/Designer has an important role in computing. Apart from analysing and designing systems,

describe another role of the Systems Analyst/Designer. [1]

Responsible for generating documentation, monitoring the

system, etc (accept relevant answers)

ii. Name one method which can be used to analyse the system

currently being used before designing the new one. [1]

Interviews, surveys, etc (accept relevant answers)

iii. An important stage in systems analysis is the changeover from

the old system to the newly-built system. One method of changeover is called phased (staggered). What happens in this

type of changeover? [1]

While the old system is still being used, certain parts are

upgraded until all the old sections are replaced.

b. Apart from writing the program, a programmer needs to test the program for errors. Syntax and run-time errors are two types of

programming errors.

Name and give an example of another type of programming error. [2]

Type of Error Example

Logical Error Area = Len + Bre

{accept relevant answers}

5. Storing and accessing data to/from a magnetic tape is

different than doing so from a hard disk or pen drive.

a. Name the two modes of file access. [1]

Serial and Direct/Random Access

b. Differentiate between the two modes of file

access. [2]

In serial access data is accessed one by

one, whilst in direct mode it is accessed

immediately.


c. Give a suitable application where each file access mode is most

adequate. [2]

Access Mode Application

Serial File Access Payroll (or relevant answers)

Direct File Access Airline booking (or relevant answers)

6. A school is setting up a new computer lab, which includes a LAN system.

[1] a. What does the acronym LAN stands for?

Local Area Network

[2]

b. Give two advantages of having the

computers interconnected together rather than standalone.

Sharing of files, program, hardware (or relevant answers)

c. For teachers to send resources to students via email, such as handouts and worksheets, another type of network is required.

What is it called? [1]

Wide Area Network (WAN)

d. At first the school decided to use fibre optic cabling for the LAN system. However, due to the large expense, the technician used Ethernet cable instead, even if the bandwidth is less than that of

the fibre optic. Explain the term bandwidth. [1]

The amount of data that can be transmitted in a fixed amount of

time

7. The minimum requirements to install the operating system (OS) Microsoft Windows 10 are shown below:

Processor: 1 gigahertz (GHz) or faster.

RAM: 32-bit version requires 1 gigabyte (GB)

and 64-bit version requires 2 gigabyte (GB)

Free hard disk space: 16 GB

Graphics card: Microsoft DirectX 9 graphics

device with WDDM driver

A Microsoft account and Internet access

a. i. Why is an operating system required in a computer system? [1]

Because the operating system manages computer hardware &

software, and provides common services for computer programs.


ii Why is the Random Access Memory (RAM) required in a PC? [1]

Volatile storage where OS, application programs and data being

used are kept for quick access – the running memory

iii. What is the difference between a PC equipped with 1GB RAM and another one with 4GB RAM? [1]

The performance of the computer with 4GB is better due to the

availability of more space for running programs

[accept relevant answers]

b. A new aircraft control system is being constructed. [1] i. What type of OS is usually used in such systems?

Real-Time OS

ii. Briefly explain one important characteristic for such an O/S. [1]

Support application programs which are non-sequential in nature;

dealing with events occurring concurrently; process and produce a

response within a guaranteed specified time interval; safely-critical

systems with hardware redundancy [any one from the above or any other relevant answer]

8. The following details are the specifications of two different CPUs:

CPU A Intel Core i9 7900X, LGA2066 Socket,

10-Core, 3.3GHz, Smart Cache 13.75MB

CPU B Intel Core i5 8500, LGA1151 Socket, 6-Core, 3.0GHz, Smart Cache 9MB

a. What is the function of a CPU?

Carries out instructions; performs arithmetic, logical and I/O [1]

operations, processes data, etc… [accept relevant answers]

b. Name and briefly explain the two units found in the CPU. [2]

ALU – with explanation & CU – with explanation

{½ for each unit and ½ mark for each description}


c. Mention two reasons and briefly explain why CPU A performs better

than CPU B. [2]

More CPU clock speed; more cores; more cache memory; etc

including explanation [accept relevant answers]

{½ for each reason and ½ mark for each description}

9. a. Using the 8-bit ASCII coding system, what is the value in binary of

the lowercase ‘g’ if the lowercase ‘a’ has a decimal value of 97? [1]

Working here

Answer: __011001112__

b. A teacher is entering the students’ details for record keeping. The following list shows the particulars to be stored for each student and

the maximum space allowed for each particular:

Name (12 characters)

Surname (12 characters) Address (36 characters) Village (12 characters)

Telephone (8 characters)

i. If the 8-bit ASCII is the coding system being used, how many

bytes and bits will each student occupy? [1]

Working here

Answer (in bytes): __80 Bytes_ Answer (in bits): __640 bits__

ii. If the list contains 1000 students, how will the teacher work out

the required space in KB? [1]

(1000*80)/1024

c. Embedded systems came into existence in the 1960s, and over the past few years their use increased exponentially.

i. Briefly describe the term embedded system. [1]

A computer system designed for a specific function/s



ii. Give an example of a digital device / gadget which can be

described as an embedded system. [1]

Washing Machine, Smart Watch, Industrial Robotic Arm, etc…


10. A school is organising a raffle as a fundraising activity and is using a computer program to randomly draw three numbers.

Draw a flowchart according to the following conditions:

The lottery has 100 tickets numbered from 1 to 100. Three DIFFERENT numbers are generated and displayed.

[5]

1 mark for using a loop to generate the 3 numbers 1 mark for checking that numbers are not the same

1 mark for displaying the numbers 1 mark for proper data flow (arrows, YES/NO)

1 mark for proper use of flowchart symbols


11. The program below is used to generate three random numbers from 1 to 100.

Analyse the program and answer the questions below.

Line 1

Line 2

Line 3

Line 4

Line 5

Line 6

Line 7

Line 8

public class RandomNum10Loop {

public static void main (String args[]){

for (int i=0; _____; i++) {

int num1 = (int) (___________________________);

System.out.println("Random number: " + num1);

}

}

}

a. i. Fill in the missing statements in Line 3 and Line 4.

Line 3: for (int i=0; i<3; i++) { [1]

Line 4: int num1 = (int)((Math.random() * 100) + 1); [2]

{1 mark for using Math.random() & 1 mark for generating valid numbers}

ii. What is the purpose of (int) in Line 4? [1]

Typecasting – assigning a value of one type to a variable of

another type

b. This program was going to be used for the raffle in question 10. However, it does not work properly. Identify and briefly explain the

fault (you do not need to write the code). [1]

There can be duplicate numbers [accept relevant answers]


Section B

12. a. There are different methods to digitally represent colours. A common

approach is the RGB (red, green, blue) model, where every colour is made up of a combination of these colours.

For example, the decimal code for:

Red is rgb(255, 0, 0) Green is rgb(0, 255, 0) Blue is rgb(0,0,255)

If these are converted to the HEX (hexadecimal) codes, their code colours would be #FF0000, #00FF00 and #0000FF respectively.

The RGB code colour for Sky Blue is rgb(135, 206, 250) and the HEX code colour for Chocolate Brown is #D2691E.

i. What would be the HEX code for Sky Blue? [3]

Working here

{1 mark each for the proper conversion of the RED, GREEN & BLUE part}

Answer: #87CEFA

ii. What would be the RGB code for Chocolate Brown? [3]

Working here

{1 mark each for the proper conversion of the RED, GREEN & BLUE part}

Answer: rgb(210,105,30)

b. i. Using 8-bit Twos complement, convert -8410 and 2010 to binary. [3]

Working here

{2 marks for converting -84 to binary & 1 mark for converting 20 to binary}

Answer for -8410: 101011002

Answer for 2010: 000101002


ii. What is the value in binary of 84 subtracted from 20 (2010 – 8410)?

Working here

{1 marks for the proper binary addition of 2010 with -8410}

Answer: 110000002 [1]

c. A company has two directors and one of them needs to be elected as the Chief Executive Officer (CEO). The three Assistant Directors must vote and a CEO is elected accordingly.

Using the conditions shown below, extract the truth table showing

the winning possibilities.

Conditions:

V1, V2, V3 are the three input votes

An output of 1 (true) indicates director A wins, while 0 (false)

indicates director B wins – The output of the truth table should show A or B which correspond to director A or director B.

Winning condition: W = (V1 AND V2) OR (V1 AND V3) OR (V2 AND V3)

[5]

Space for Truth Table:

V1 V2 V3 W

0 0 0 0 (B)

0 0 1 0 (B)

0 1 0 0 (B)

0 1 1 1 (A)

1 0 0 0 (B)

1 0 1 1 (A)

1 1 0 1 (A)

1 1 1 1 (A)

1 mark for proper input combination 1 mark for showing V1.V2 1 mark for showing V1.V3 1 mark for showing V2.V3

1 mark for showing proper output

OR

Allocate 5 marks if students manage the

right answer directly without the need to work out V1.V2, V1.V3 & V2.V3


13. A car rental garage has its system automated by using a database. The system

consists of three tables: CLIENT Table, CAR Table and LOAN Table which are related together. For a better service, the garage has a maximum of five cars of

the same car.

The CLIENT Table details are given below. Using this scenario, answer the questions below.

CLIENT Table

Fields Data Types

Client_ID Text

Surname Text

Name Text

Address1 Text

Address2 Text

Contact_Num Text

a. Fill in the missing fields and data types for the CAR Table. Indicate

which field is the primary key. [3]

CAR Table

Fields Data Types

Number_Plate or

Registration Num (or relevant answers) Text

Model Text

Colour Text

Manual or Diesel (or relevant answers) Boolean

Size Text

Quantity Number

PRIMARY KEY:

Registration

Num

{½ mark for each field and data type & 1 mark for indication of Primary Key}

b. Draw a table like the one above with a minimum of five (5) fields for

the LOAN Table. [5]

Space for table:

LOAN Table

Fields Data Types

Loan_ID Text

Client_ID Text

Number_Plate Text

Date_Out Date

Date_In Date

(or other relevant fields)

1 mark for proper primary key 1 mark each for proper foreign keys {2 marks}

1 mark for at least two other relevant fields 1 mark for the overall use of proper data type


c. What is the advantage of having tables related in a database? [1]

To reduce data redundancy (accept relevant answers)

d. Describe the relationships between the three tables. [2]

1-to-many relationship between CLIENT Table and LOAN Table

1-to-many relationship between CAR Table and LOAN Table

e. Inputting correct data is crucial in databases.

i. What is the person who enters data in a database called? [1]

Data entry clerk

ii. It is quite common for the person inputting records into the

database to make mistakes. Name and describe, by using an

example, one type of transcription error. [1]

Omission, transposition or substitution with example

iii. What is validation check? [1]

Checking the validity of a value (data) input in a computer

iv. Mention one validation check required on the field ‘Quantity’ in

the CAR Table? [1]

Range Check (1 to 5) or Type Check (Numbers only)

--- END OF PAPER ---

year 11 computing marking scheme...pen drive magnetic file allocation table hierarchical sector...

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