Give One reason why we use binary to represen data in computers

State the denary representation of the hexadeciaml number A7 show your working

 A = 10    7 = 7

   8 4 2 1   8 4 2 1

        1 0 1 0  0 1 1 1    

128 64 32 16 8 4 2 1

1 0 1 0 0 1 1 1

128 + 32 + 4 + 2 + 1

= 167

Which three of the following are common data types that most programming languages provide

• Boolean
• Except
• Length
• Integer
• While
• Character
• Maximum

• Boonlean
• Integer
• Character

For each feature of this phone listed in the table below, show whether it is an input method, an output method or both.

Vibration alert Input output both

Touch Screen Input output both

Microhone Input output both

Speaker Input output both

vibration         Output

Touch Screen   Both

Microphone      Input

Speaker          Output

Give three developments in hardware that have made smart phones possible in the last 10 years

More power efficient processors

smaller memory

solid state memory

affordable touchscreens

you only need 2

If two personal computers are advertised with differnt hardware specifications

PC A has a quad-core processor with closk speed of 2 GHZ

PC B has a single core processor with a clock speed of 4.1 GHZ

Explain which processor you think is likely to run instructions more quickly

PC A as it has 4 cores that will allow it to process four instructions at the same time

Why is it important for both of these personal computers to have a sufficient amount of RAM

The following is a Function

FUNCTION IsPrefix (name, value)

    IF name[1] = value

              RETURN true

    ELSE

              RETURN false

    ENDIF

endfunction

• Give the name of one parameter used
• State the data type of name
• State the data type of return value

• name, value
• array
• boolean

To make code easier to read

to allow code to be reused

to reduce programmer error

• Explain, with reasons two disadvantages of using the ring topology in a computer network

• one faulty device/connection means the network can fail
• Connections are shared between all devices so not secure
• data has to travel through many devices to get to its destination so it will be slow

Some network terms have shown below

1. Protocol
2. Client
3. Server
4. Handshaking process
5. Web applicaiton
6. Topology

give the correct label to the following

1. An agreed method of communicaiton
2. the machine that mostly requests information
3. software that is accessed over a network such as the internet

An agreed method of communication = 1 protocol

The machine that mostly requests information = 2 client

software that is accessed over a network such as the internet =  5 Web application

For each of the following events state whether it would be typically occur at the client end or the server end or at both

updating a database    client   server     both

Validation of user fields   client   server    both

Checking username and Password    client    server  both

updating a database    - Server

Validation of user fields  - both

Checking username and Password - SERVER

The following is a program that is suppsed to add together all the elements of an array to give a total. the total is stored in a vaiable called tot. The program contains a run-time error and a logical error.

01   tot  =  0

02   arr  =  [3,  19,  2,  8]

03   FOR I = 1 to LEN (arr) + 1

04           tot = arr [i]

05   ENDFOR

• What is syntax error
• what is the final value of the variable i
• why might a run- time error occure on line 4
• why are logical erros often difficult to find
• what line nr does the logical error occure and what is the correct version of this line of code

• An written error in a program that breaks the rules of the programming language
• 5
• the program attempts to access element 5 of the array arr which does not exist
• because there is a logical erro
• because the program may appear to run normally
• Line 4 the correct version should read
•      tot = tot + arr [i]

Write a program for a game (using either pseudocode or a flowchart) that does the following

• assigns the value "mobile" to a variable called answer
• then assigns user input to another variable called guess
• if the user enters the value "mobile" then the program outputs "winner" otherwise it allows the user to have another guess
• allows the game to continue until the user guesses correctly

answer = "mobile"

guess = "USERINPUT

WHILE answer isnot = guess

guess = USERINPUT

END WHILE

OUTPUT WINNER

OR ANY OTHER LOGICAL DIAGRAM PRACTICE THIS

• A programmer is going to make a simple improvement to a game to keep track of a number of guesses

State two other simple improvements that would be made to the program

Keep Highest Score

allow another user to enter the value to be guessed

allow another go

display corrected guessed letters

In a table called Product eache row has a ProductCode that is unique

What is this ProductCode better known as

What two SQL commands would you use to insert data into a table?

INSERT (TABLE NAME)

Values ( data to be entered into the table)

A programmer is developing a website for an online shopping company. He is using some code from an external source to create the input fields on a form.

Give two reasons why the programmer might want ot use an external source of code for his website

So data can be edited by users

save memory spce if data is not large

Programmer relies on another company/organisation or person to update their code.

May reduce the security of the site

ASCII is 7 bit binary therefore the highest number of characters it can represent is 128

Many languages throughout the world have more than 128 characters

Scocial networking websites have very recently been used by large groups of people around the world to organise protests against their governments

Discuss three technical reason s why social networking sites may have been used for this purpose

Free of cnsorship

allows media as well as text to be shared almost instantly

allows communicaton to many recipients simultaneously speeding up communication

speeds up the spread of informaiton

A programmer wants to develop a large peice of software

Discuss two possible software developemt lifecycle models she could use. In your answer compare the advantages and disadvantages of both models

Waterfall Model - Each phase clearly seperated, inflexible and difficult to go back a step if needed

Spiral Model - More client consultation, ability to return and fix problems