• By setting the validation rule for the input controls on the property sheet in design view
• By use of VBA to restrict user inputs for a given control on a form
• By use of queries to restrict options available for the user in a combo box or listbox
• Setting correct data types for the fields in table the design
• Enforcing referential integrity in database relationships
• Use of input mask for the controls on the property sheeet in design view

Many components that go into computer systems are toxic and dangerous to the environment if released or disposed of inappropriately.
Heavy metals are used in batteries and circuits and these can pollute groundwater or kill animals if left exposed on landfill. Large quantities of plastics are used in systems, which take a long time to break down, some of the plastic will eventually break down into toxins as it degrades.

(a) Phishing

• Phishing is a strategy that encourages a computer user to part with sensitive information such as bank details hence the term ‘phishing’ – i.e. fishing – trying to catch someone out. For example, a perpetrator sends a user an email that appears to be genuine, for example, pretending to be a bank or a lawyer requesting that the user verify bank account details or send money to assist in the completing of a legal case.

(b) DoS

• DoS is a means of attack on a specific user/system/website which involves overloading a target with too much network traffic resulting in system slowdown, shutdown or a violation of security.

• star - if one computer goes down the others can still be used
• ring - if one computer goes down the others can not be used

• a computer that responds to requests to provide information and services over the Internet - an Internet server
• defines how messages are transmitted and formatted over the Internet-HTTP
• software that enables users to access/view documents and other resources on the Internet - Browser     
• numerical ID for each device on the Internet-IP address
• unique ID for a network interface card  -MAC address

• A barcode is one-dimensional while a QR code is two dimensional
• Barcodes are a set of vertical lines and QR code contains squares
• QR codes can be read from any angle . Barcode is only above or below and lined up horizontally

(a) byte

• fixed number of bits, 8 bits
• represents a character

(b) compiler  program

• converts/changes/translates high-level language into machine code/machine language/low-level language/object code
• changes each high-level language instruction into machine code instructions
• produces an independent program capable of being executed by itself
• all (syntax errors) listed
• converts the whole program before execution/in one go
• converts source code to object code

(c) handshaking

• exchanging of signals to establish communication between two devices/computers e.g. printer and computer, modem and computer

(d) technical documentation

• documentation to ensure that the system can be maintained/updated/altered/developed/upgraded
• trouble shooting/correcting errors/correcting faults
• explanation of what the program does/how the system works
• contains file structures
• algorithms/flow charts/pseudo code
• program listings
• hierarchical chart

(e) simulation

• studying the behavior of a system by using a model/represents real-life/mathematical representation
  e.g. flight simulator (or others), hazardous applications results can be predicted

• High-level languages have built-in functions;
• High-level languages have built-in libraries;
•  High-level languages have more support/help;
• High-level languages have structures (such as selection and iteration);
• High-level languages can be less machine-dependent/more portable;
• It (usually) requires fewer lines of code to be written;
• It is (usually) quicker to develop code in high-level languages;
• It is easier to find mistakes in code;
• The code is easier to maintain//understand;
• • It is easier to structure code in high-level languages;

• it is easier / quicker to read/write/understand
• it is easier / quicker to debug
• code is portable.

1. Enable resource sharing
2. Facilitate remote communication
3. Enable distributed processing
4. Provide better data security and management

give uninterrupted path through the system of linked traffic lights/
green link - wave
turn all lights to red
activate emergency generator
alarm

• A compiled program will only execute on a processor of specific type/family/with same instruction set
• A program run using an interpreter can execute on a computer with any type of processor

• once instructions are given, the processing runs automatically hence requiring little supervision
• tasks are processed as a group hence reducing the cost
• It is faster since the since runs automatically
• there is increased output since the processor works without any interruption

• confidentiality - The principle of protection from unauthorized access or disclosure
• Integrity - the principle of ensuring that unauthorized or undetected changes to data or system configurations do not occur.
• Availability - the principle of ensuring that data and services remain accessible to authorized users at all times

• car factories/factories
• chemical/nuclear factories
• production lines
• warehouses
• deep in the ocean/down mines
• on other planets/in space
• road junctions

Any four of:
Sequential:
• Individual instructions are executed one after another
• Flow control is accomplished by jump/branch/goto instructions
• Results are usually achieved less quickly than parallel processing (do
not award twice)
Parallel:
• Individual instructions can be routed to different processors for
simultaneous execution
• Results are usually achieved quicker than sequential instruction (do not
award twice)
• Requires multi-core processors or multiple microprocessors
• Tasks may be split into different parts with each part executed on a
different processor
• Results need to be merged back together after completion

Solid state
 

• Simple technology is needed to develop both hardware and software.
• Digital devices are more reliable, small in size and use less power as compared to analog devices.
• Devices that read, process or output data in digital form are used in computers and other digital devices such as calculators.

• backups/dumps of files
• copy of files on CD/tape streamer
• file generations