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FINAL QUIZ
Marlene Galea
Give 2 possible disadvantages of
computerising a system
Give 2 possible disadvantages of
computerising a system
- Dependency : users may grow increasingly dependent on the
computerised system such that work suffers a lot of the system is
temporarily unavailable
- Data security against hacking and data theft leads can be expensive,
and there is still always the risk of security breaches.
Why is a compiler better suited than an
interpreter for program distribution?
Why is a compiler better suited than an
interpreter for program distribution?
A compiler produces object code.
• Object code can be saved and directly executed later on. So object code can
be distributed to run without further translation. So the actual code will not be
seen by the user if a compiler is used which is desirable when distributing a
program.However no object code is created with an interpreter.
• Also, if using a compiler, when a loop is run the translation is only done once,
with an interpreter the loop is translated every time the program loops.
Therefore an interpreted program will run slower when executing a loop.
What is the address space of a CPU
with a 32 bit address bus?
How does the address bus effect
computer performance?
What is the address space of a CPU
with a 32 bit address bus?
How does the address bus effect
computer performance?
232
Address space determines the number of memory locations that can be
directly accessed by the CPU, so the greater the address space the more
RAM the CPU can use.
Having more RAM ensures more applications can run simultaneously
and smoothly.
Give 2 advantages of computerising a
system
Give 2 advantages of computerising a
system
• Computers are more reliable and consistent than humans: so they
may help avoid errors an accidents.
• When dealing with large volumes of data it is faster and more efficient
to search for data on a computerised system than have humans do so.
What is the Internet? How is it
different from the WWW?
What is the Internet? How is it
different from the WWW?
The internet is a global network of computers connected together in
such a way as to be able to exchange data.
The www is only part of the internet it is a system of interlinked
hypertext documents contained on the internet.
Give 2 uses of the Internet in:
• Education
• Commerce
Give 2 uses of the Internet in:
• Education
• Online testing: online tests are efficient because they can be corrected
by the system and hence give a student immediate results
• Video conferencing: this can be used to expose students to realities
outside their school without the expense and time wastage of
travelling: e.g. to discuss issues with experts or other students in other
countries
• Commerce
• E-commerce: the selling of items on the internet using auction sites etc
• Advertising: online advertising is a very good way of reaching potential
client.
What is Assistive Technology (AT) ?
Name an output and an input device
used in AT
Assistive Technology (AT) refers to technology that allows greater
independence for people with disabilities by enabling them to perform
tasks that they were unable to accomplish before, or had great difficulty
accomplishing, by providing new methods of using technology
Input device: braille keyboard
Output device: braille printer
What is Assistive Technology (AT) ?
Name an output and an input device
used in AT
What is the role of the ALU in a
computer?
What is the role of the ALU in a
computer?
The ALU (Arithmetic Logic Unit) carries out the
computer’s mathematical functions and
comparison operations
What is the role of the Control Unit
in a computer?
What is the role of the Control Unit
in a computer?
The Control Unit is responsible for:
• locating, decoding and executing each instruction in a program
• data transfer between memory and peripheral devices
What are mnemonics and symbolic
addressing?
What are mnemonics and symbolic
addressing?
• Mnemonics are short, abbreviated words used in Assembly Language
instead of binary patterns (e.g. LDA)
• Symbolic addressing is the use of variable names to refer to memory
addresses. (e.g. num1)
Distinguish between the following
three types of addressing
• Direct Addressing
• Immediate Addressing
• Symbolic Addressing
Distinguish between the following
three types of addressing
• Immediate Addressing
the instruction itself contains the value to be used.
Eg. MOV A, #20h the value to be used is 20h
• Direct Addressing
the instruction tells where the value can be found, but the value itself
is out in memory.
Eg. MOV A, 30h the values is found in memory location 30h
• Symbolic Addressing
symbolic addressing the address of a store location is specified by
means of an identifier, rather than the numeric value of the memory
address.
Eg. MOV A, num1 the value is stored in the variable num1
Distinguish between opcode and
operand
Distinguish between opcode and
operand
Opcode is the code specifying the action to be carried out (eg. Add)
Operand is the value on which the action is to be carried out or the
address in memory where this value is stored (eg. 5)
Give 2 advantages and 2 disadvantages
of using a LLL rather than a HLL
Advantages
LLL run faster because they are closer to machine code
Programs in LLL need less system resources to run
Disadvantages
Difficult to program in because they require a good knowledge of
machine architecture
Programs in LLL are not portable
Give 2 advantages and 2 disadvantages
of using a LLL rather than a HLL
Give 1 advantage and 1
disadvantage of a bus network
Give 1 advantage and 1
disadvantage of a bus network
Advantage
Less expensive to set up
Disadvantages
Performance degenerates as more computers are added
What personnel is/are responsible
for the following
• Creating Test Data for a system
• Writing program code
• Creation and Update of websites
• Data entry
What personnel is/are responsible
for the following
Creating Test Data for a system Systems Analyst
Writing program code Programmer
Creation and Update of websites Web Master
Data entry Data Entry Clerk
What is a CPU register?
Mention 2 CPU registers and briefly
describe their function
What is a CPU register?
Mention 2 CPU registers and briefly
describe their function
A CPU register is a small amount of memory on the CPU where data can
be temporarily stored
Examples
Program Counter – holds the address of the next instruction
Instruction register – holds the address currently being executed
What is a database? Give 1 advantage
of computerising a database
What is a database? Give 1 advantage
of computerising a database
A database is an organised collection of data and links between
them such that information can easily be obtained from it.
Advantages
It is faster to obtain information and query the system
Use only AND, OR and NOT gates to
produce a logic circuit which gives ‘1’
only when one OR the other of two
inputs is one but not both.
This is asking for the XOR gate in terms of the OR, AND and NOT
gate.
Use only AND, OR and NOT gates to
produce a logic circuit which gives ‘1’
only when one OR the other of two
inputs is one but not both.
Give the truth table for the above
A B A’ B’ A’B AB’ A XOR B
0 0 1 1 0 0 0
0 1 1 0 1 0 1
1 0 0 1 0 1 1
1 1 0 0 0 0 0
Give the truth table for the above
Suggest 2 possible disadvantages of e-
• Spam may be sent and unnecessarily fill inbox
• One may receive a virus and other malware via email
Suggest 2 possible disadvantages of e-
Compare the 3 types of looping
constructs
Conditional Loops
Undetermined Loops
Do…while loop
Repeats one or more times
Condition at end of loop
While…loop
Repeats 0 or more times
Condition at start of loop
Unconditional Loop
Predetermined Loop
– For loop
Compare the 3 types of looping
constructs
Why are tables in a database linked
through relationships?
• So as to have no redundant data
• So database occupies less storage space and is faster to process
• Database is easier to update
• Saves time and money - data input costs time and money.
Why are tables in a database linked
through relationships?
Complete the diagram explaining the
creation of file generations?
Transaction File
Master File
Sorting process Sorted Transaction File
Update Process
New Master File Error Report
Complete the diagram explaining the
creation of file generations?
Distinguish between serial and direct
access
• Serial access
means going through everything one by one, starting at the beginning, until you
reach the item you want.
• If you wanted to print all the names in a database, using serial access would be
fine because you are starting at the first and going right through to the end.
• Direct access
means going straight to the item you want without having to go through other
ones.
Distinguish between serial and direct
access
Mention 3 things that determine CPU
performance.
•Wordlength: the number of bits the CPU can handle at a go
•Cache memory: fast, volatile memory that holds a copy of recently accessed
data in anticipation of its being used again in the near future
•Clock speed: the number of times the CPU clock changes state per second
Mention 3 things that determine CPU
performance.
Give 3 uses of the Internet
• Research through vast amounts of sources: Looking up information
for school projects, business interests etc
• E-commerce
• Social Networking
Give 3 uses of the Internet
Which are the 3 programming
constructs?
•Loop (repetition)
•Decision
•sequence
Which are the 3 programming
constructs?
Is the check digit ‘6’ for the number
12346 correct?
(Using modulus 11 method)
1 2 3 4 6
5 4 3 2. 1
5 8 9 8 6
36/11
3 r 3
Therefore check digit is incorrect because there is a remainder
Is the check digit ‘6’ for the number
12346 correct?
(Using modulus 11 method)
Briefly describe these forms of
documentation
• Inline documentation
• User manual
• Installation manual
Briefly describe these forms of
documentation
Inline documentation
– these are comments in the program code that explain how the code works
User manual
– instructions to the user that show how to operate the program. This manual should avoid too technical terms.
Installation manual
– Instructions how to install the program including what hardware and software resources it requires
Give 1 application for
Dot matrix printer
MICR
Laser Printer
Barcode Reader
Give 1 application for
Dot matrix printer
Production of bills
MICR
Processing bank cheques
Laser Printer
On an office network
Barcode Reader
Bill production at a POS
Give 1 use for
LOGO
FORTRAN
COBOL
PROLOG
Give 1 use for
LOGO – to teach programming to young children
FORTRAN – to create programs to be used in scientific and mathematical applications
COBOL- to create business applications
PROLOG – to create programs used in AI
Put the steps of the system life cycle
in order
1. Maintenance of the new system
2. Project approval
3. Implementation
4. Designing and testing
5. Training staff
6. Documentation, both technical & user manuals
7. Feasibility study
8. Problem identification
Put the steps of the system life cycle
in order
1. Maintenance of the new system
2. Project approval
3. Implementation
4. Designing and testing
5. Training staff
6. Documentation, both technical & user manuals
7. Feasibility study
8. Problem identification
8, 7, 2, 4, 6, 5, 3, 1
Outline the main steps in the
fetch/execute cycle
Outline the main steps in the
fetch/execute cycle
• CU fetches instruction from memory location pointed by PC
• Copy of the instruction is placed in the IR
• CU fetches required data/address of data
• PC is incremented to the next instruction
• CU activates necessary circuits to execute the instruction
• Back to 1st step
Distinguish between general purpose
and special purpose computers
•Special purpose computers: are designed to do one particular function
•General purpose computer can carry out a number of applications depending
on the program being run
Distinguish between general purpose
and special purpose computers
Distinguish between FAT and NTFS
•NTFS allows the use of larger storage devices than FAT
•NTFS is a more recent filing system that is ideal for multi user systems
allowing:
• User quotas on disks etc
• Improved file security
Distinguish between FAT and NTFS
Draw the logic circuit and give the
truth table for
X = (A’.B) + (C+B’)
A
C
B
Draw the logic circuit and give the
truth table for
X = (A’.B) + (C+B’)
A B C A’ A’.B B’ C+ B’ X
0 0 0 1 0 1 1 1
0 0 1 1 0 1 1 1
0 1 0 1 1 0 0 1
0 1 1 1 1 0 1 1
1 0 0 0 0 1 1 1
1 0 1 0 0 1 1 1
1 1 0 0 0 0 0 0
1 1 1 0 0 0 1 1
Draw the logic circuit and give the
truth table for
X = (A’.B) + (C+B’)
Subtract, using 8 bit two’s complement,
13 from 54
54 – 13
13 = 00001101
54 = 00110110
Two’s complement of 13 00001101
11110010
+1
11110011 (-13)
00110110
11110011
100101001
Subtract, using 8 bit two’s complement,
13 from 54
Distinguish between data validation
and data verification
•Validation ensures that data entered is reasonable and complete
while
•Verification ensures that the data is transferred correctly
Distinguish between data validation
and data verification
Suggest 1 use for
Batch Processing Operating System
Hard disk
Real time Operating System
Logic Gates
Light Pen
Mainframes
Palmtop
Batch Processing Operating System Payroll system
Hard disk Frequently used applications
Real time Operating System Military aircraft targeting system
Logic Gates addition inside the CPU
Light Pen Booking systems
Mainframes Bank system
Palmtop Order taking at a remote POS
Suggest 1 use for
What is process control?
The automatic monitoring and control of a system that responds to feedback
input from sensors
What is process control?
Binary Decimal Hexadecimal
111001
56
13F
Convert
Binary Decimal Hexadecimal
111001 57 39
111000 56 38
100111111 319 13F
Convert
Compare tailor made and off the
shelf software
Tailor Made Software Off the Shelf
More expensive Mass produced, therefore cheaper
Not readily available Readily available
Not possible to get user reviews One may get user opinions before buying
Compare tailor made and off the
shelf software
Suggest 3 ways how wordprocessing
has facilitated office work
• Mail Merge: Automised production of personalised documents
• Language tools: spellchecker and thesaurus help user improve content
quality
• Presentation tools: ability to modify and edit, fonts, paragraphs and page
design allows one to produce more attractive documents.
Suggest 3 ways how wordprocessing
has facilitated office work
Give 2 functions of an operating
system
• CPU Management: allocates CPU time to running processes
• Memory Management: allocates memory space to programs
Give 2 functions of an operating
system
Mention
1 portable magnetic storage device
1 read only electronic storage device
1 serial access device
1 optical storage device
1 volatile storage device
1 portable magnetic storage device: floppy disk
1 read only electronic storage device: ROM
1 serial access device: magnetic tape
1 optical storage device: CD
1 volatile storage device: RAM
Mention
Distinguish between global and local
variables
Local Variable: is declared at method or program section level and so has a
scope limited to that method or program section within which it is declared.
Global variable: is declared at class level and can be accessed from anywhere
within the class.
Distinguish between global and local
variables
Suggest 2 means of safeguarding data
security
• Using a firewall
• Using encryption
Suggest 2 means of safeguarding data
security
What is a sector?
The smallest addressable section of a disk.
What is a sector?
What is a virus? Mention 1 other type
of malicious code besides viruses
Malicious code written to automatically copy itself between and within
computers and hence render them unreliable
Other malicious code: trojan
What is a virus? Mention 1 other type
of malicious code besides viruses
Suggest 3 ways in which a spreadsheet
can improve a family’s budgeting
efforts
• Efficient calculation of data
• Can easily represent data in graphical form, making it easier to analyse
• Can easily obtain answers to ‘what if’ questions
Suggest 3 ways in which a spreadsheet
can improve a family’s budgeting
efforts
What is software piracy? Suggest 2
ways a company may protect its
software from piracy
Software piracy is the unauthorised copying and distribution of software.
Companies can try to protect themselves against piracy using:
• Key disk
• Software registration
What is software piracy? Suggest 2
ways a company may protect its
software from piracy
Distinguish between flowchart and
pseudocode
Both are ways of describing an algorithm however a flowchart is diagrammatic
whilst pseudocode is purely textual.
Distinguish between flowchart and
pseudocode
Write a program that produces the
following output:
(where X is input by the user)
1 x X = answer
2 x X = answer
….
12 x X = answer
An integer variable called ‘sum’
A constant called vat with a value of 18%
A constant called ‘name’ with a value of ‘Mario’
An array of names that can hold 10 names
A two dimensional array that can hold 10 names and surnames
Write a program that produces the
following output:
(where X is input by the user)
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