Past Paper Thursday 17th May 2012 - Afternoon

Question 1

Identify two devices that can be built into a tablet computer and state how they can be used to input information? (4)

Answer 1

-Touch screen
… respond to fingers / stylus on specified icons
… for example a software keyboard
… eg converts handwriting to text

-Hardware buttons
… a small number around the edge of the tablet
… for most common commands
… eg bring up menu / next / previous / play / pause
etc…

Question 2

State three functions of a server in a normal network? (3)

Answer 2

-Controls access to the network / verify passwords
entered on any computer.
-Provides files to the other computers on the network
-Installs software on workstations.
-Make the printer accessible to the other computers.
-Controls the access of computers to the Internet/to
each other.
-Stores, delivers and sends emails for all users on
the network.

Question 3

Explain what is meant by a peer to peer network? (2)

Answer 3

• All computers have equal status/no server
  controlling.
• To share data/files/devices between each other.

Question 4

Describe how the System maintenance utility is used? (2)

Answer 4

-(Searches for and) deletes files/programs which are
no longer used.
… eg deletes temporary files / installation files.
… deletes settings / registry values which are no
longer used.

Question 5

Describe how the Automatic update utility is used? (2)

Answer 5

-Automatic update
-Checks on the (software manufacturer’s site on the)
-Internet for newer versions of programs which are
installed
-If found it download / installs the software.

Question 6

Convert the deanery number 55 to an 8 bit binary number? (2)

Answer 6

-0011 0111

Question 7

Convert the deanery number 55 into hexadecimal? (2)

Answer 7

-37

Question 8

State two tasks which are carried out by the CPU when processing data? (2)

Answer 8

• Fetches instructions (from memory).
• Fetches data (from memory).
• Decodes instructions.
• Executes instructions.

Question 9

Explain how the clock speed of a CPU affect its performance? (2)

Answer 9

-The higher the clock speed the faster the CPU will
run.
-Represents the number of fetch execute cycles /
instructions the CPU can process in a given time.

Question 10

Explain how the cache size of a CPU affects it performance? (2)

Answer 10

-The more cache the CPU has the less time is spent
accessing memory / programs run faster…
-Cache is faster than memory/ built into the
CPU/contains frequently accessed data

Question 11

State what DBMS stands for? (1)

Answer 11

-Database management system.

Question 12

Describe the features of a DBMS that can be used to create customized data handling applications and explain why using DBMS is desirable?
(The quality of written communication will be assessed in your answer to this question.) (6)

Answer 12

-Points may include:
-Features
–Provides a set of tools for
accessing/maintaining the
database, eg to define/create
tables, run queries or define
reports
–The application is independent
from the data base itself
–Provides data integrity control (eg
integrity checks, validation checks)
–Controls access to data, including
security and multiple user access
-Why desirable
–These can be set up before hand
by expert and used by end user
–Separating application and
database means the database can
be accessed separately by other
means eg a desktop application
and web application accessing the
same data / other suitable
example
-Data is protected from corruption eg by
multiple access

Question 13

Explain why computers use binary? (2)

Answer 13

So that computers can be based on logic circuits.
- … ( each part of the circuit) can be in one of two
states
- … 0 and 1/true or false.

Question 14

Describe how instructions are stored in binary? (3)

Answer 14

The instruction consists of an operator/op code

• … and an operand
• both stored as bit patterns
• (op code) from a given instruction set
• Each op code has a unique bit pattern

Question 15

Describe two differences between high-level code and machine code? (4)

Answer 15

In high level code Instructions use words
-In machine code instructions are in binary code
-High-level code is designed to be read by human
programmers
–Machine code is to be read/executed by the
computer
–High level code can be portable/translated for
different machines
–Machine code is specific to a particular machine
(marks in pairs)

Question 16

Describe how and interpreter translates the high-level code to machine code? (2)

Answer 16

-Translates one line of HL code at a time…
… and executes it
… stops when it finds an error
… can be resumed

Question 17

State the name of a different type of translator, other than an interpreter, which can be used to translate high level code to machine code? (1)

Answer 17

-Compiler.

Question 18

The online game is developed by a large team of programs.

• Explain, with examples, why a large team of programmers need to agree to standards when developing the game.
• the quality of written communication will be assessed in your answer to this question. (6)

Answer 18

=Points may include: 
-Programmers need to understand each 
other's code 
… so need clear commenting / 
consistent formats eg for variable 
names 
… suitable examples 
-Programmers need to ensure that their 
code will work with the code written by 
others 
… agree clear interfaces between 
modules 
… and stick to agreed interfaces/ 
protocols 
… suitable examples 
-The success of one programmer's work 
depends on the others 
… so a need for professionalism 
… suitable examples

Question 19

State whether the operations below use sequence, selection or iteration.
=Performing a series of different set-up operations when the computer is switched on. (1)

Answer 19

Sequence.

Question 20

State whether the operations below use sequence, selection or iteration.
=Beeping repeatedly after a message is sent, until the driver presses a button to show that the message has been read. (1)

Answer 20

Iteration.

Question 21

State whether the operations below use sequence, selection or iteration.
=Deciding whether to use the DayTimeRate or the EveningRate functions to calculate a customers fare. (1)

Answer 21

selection

Question 22

The computer measures the distance traveled as a real number and then rounds it up to the next integer.
State what is meant by a real number. (1)

Answer 22

A number which can contain a fractional part.

Question 23

The computer measures the distance traveled as a real number and then rounds it up to the next integer.
State what is meant by a integer. (1)

Answer 23

A whole number.

Question 24

The cost of a day time Journey is £3 for the first kilometer and £2 for every kilometer after that. If there are five or more passagers in the taxi, an extra 50% is added to charge.

Write an algorithm to calculate the cost of a day-time journey.

Your algorithm should:

• Allow the number of passengers and the distance of the journey to be input as whole numbers,
• Calculate the cost of the journey,
• Output the cost that has been calculated. (7)

Answer 24

=EXAMPLE: 
INPUT Distance 
INPUT Passengers 
Extra = Distance – 1 
CostofExtra = Extra * 2 
Cost = 3 + CostofExtra 
IF Passengers > 4 THEN 
 Surcharge = Cost / 2 
 Cost = Cost + Surcharge 
END IF 
OUTPUT COST 

=Award marks for:

• Inputs distance and passengers
• Calculates distance – 1 (or equivalent)
• Calculates previous answer * 2(or equivalent)
• Calculates previous answer + 3
• Checks if more than 4 passengers…
• … and adds 50% correctly
• Outputs cost