CP2 Computing June 2005

1	A holiday company sends emails to customers advertising holidays.
(i)	Give two reasons, apart from cost, why the company may prefer to use email for this communication instead of using conventional post.	[2]
	The customer will receive the information much quicker by email. File attachments, such as videos, can be made to an email giving details about a particular holiday.
(ii)	Describe one problem that may arise from using email in this way.	[1]
	A virus may be sent along with the email which infects the customer's computer.

2.(a)	Files on a hard disc are usually stored using a directory with a hierarchical structure.
(i)	Use a diagram to show what is meant by the term hierarchical structure.	[1]
	A hierarchical structure has a 'root' (starting point) and items on various levels. An example is the file structure of a hard disk. Each folder contains the files or folders linked below it.

(ii)	Explain why this is a sensible way of storing files.	[1]
	Finding files is much easier, and faster.
(b)	State one attribute that a file may have.	[1]
	A Read-Only attribute will stop a file being changed if it is set.

3.	Seren Computers is a small company selling personal computers. Customers can have a computer built to their own specification. Kim orders a personal computer that includes a processor, memory, monitor, keyboard, mouse and a hard disc drive. Other types of secondary storage are available at extra cost.
(i)	State two additional secondary storage devices that Kim may wish to purchase, giving a reason in each case.	[4]
	Floppy disc drive (or USB Memory Stick) Data can be saved and transported to other computers. Tape streamer. Large data capacity can allow backups to be regularly made.
(ii)	Kim's computer has some RAM cache memory. State what is meant by RAM cache memory, and explain why it is used.	[2]
	An additional memory chip that acts as extra RAM memory - the contents of the memory can be changed. This acts as extra memory when a program is running enabling the program to run faster.

4. (a)	A pizza delivery firm takes orders over the telephone. The customer's order details are recorded on paper. A copy of the order is given to the driver so that the pizza can be delivered.
(i)	Describe two possible problems that the firm may experience with the current paper-based system.	[2]
	Storage problems - large numbers of pieces of paper are difficult to keep tidy and searching for one particular order may take some time. Orders may easily become lost, misplaced or damaged.
(ii)	The firm decides to replace the paper-based system with a new computer system.
	(I) Describe the most suitable software that the firm would require.	[1]
	Database software.
	(II) Explain how this new computer system would solve the problems encountered with the original paper-based system.	[2]
	Orders can be stored on a computer disk, and can be sorted in order so that searching for a particular order is fast. Database records cannot go astray, and if backups of the data are done on a regular basis, then corrupted data records can always be retrieved.
(b)	Customers can pay by credit card and the firm stores the details on the new computer system. The firm will then have to comply with the Data Protection Act. Describe three ways in which the Act will apply to the data stored by the firm.	[3]
	The data must be kept secure. The data cannot be used for other purposes. The data must not be kept longer than is necessary.

5. (a)	Draw a diagram that shows the topology of a ring network.	[1]

(b)	Explain why it is necessary to have standards (or protocols) for communication to take place along computer networks.	[1]
	Without protocols computers would not be able to interpret any data that is sent to them.
(c)	What is an interface between a peripheral and a computer?	[1]
	A connection where the peripheral is plugged into the computer.
(d)	Briefly explain the term handshaking when used in connection with a computer and a printer.	[3]
	A computer sends a signal to the printer to find out if the printer is ready to receive data. The printer responds with a signal to the computer to indicate whether it is ready. If the printer is ready the data is sent from the computer to the printer.

6. (a)	Explain the difference between serial file organisation and sequential file organisation.	[2]
	Serial file - records are added to the end of a file in the order they are received. Sequential data - records are stored in sorted order of a key field.
(b)	State a computer application which uses sequential file organisation. Explain why this file structure is the most appropriate for this application.	[2]
	Information retrieval system - such as a system for train timetables. If the data is sorted, the searching for information is much faster.
(c)	Records within a file can be fixed length or variable length.
	(i) Describe the difference between fixed and variable length records.	[2]
	Fixed length - Each record in a file is the same size (number of bytes) Variable length - Records are different sizes, using separators between the fields and records.
	(ii) State an application in which fixed length records would be used. Explain why fixed length records are suitable for this application.	[2]
	A school pupil record system stored on a computer with large capacity hard drives. The use of fixed length records means that searching for data is much faster.

7.	Explain what is meant by each of the following terms.
(i)	data bus;	[1]
	A path (wires) down which data is transmitted.
(ii)	control bus.	[1]
	A path down which signals are transmitted to control the actions of the computer.

8.	A supermarket uses a bar-code reader at each checkout.
(a)	Apart from itemised bills, describe two other advantages for the customer of the checkout operator using a bar code reader rather than typing the price of each item.	[2]
	Faster service at the till so there will be less queuing. Greater accuracy - there should be less chance of a mistake in the customer's bill.
(b)	Explain in detail how data from the bar code is used to update the stock database.	[3]
	The bar code data is transmitted to the main server. The item with this bar code is found by searching the database of stock. The stock level is reduced accordingly.

9. (a)	A school library has a number of computers with access to the Internet and the school's Intranet.
(i)	Describe two uses a pupil could make of the Internet to help with their studies.	[2]
	Research - to find up-to-date information about a topic they are studying. Ask for information by leaving messages on a forum or bulletin board, or using chat lines to communicate with other people.
(ii)	Describe two examples of information that the school may have on its Intranet.	[2]
	The school calendar of events. Subject study notes or links to helpful web sites.
(b)	Describe two possible health concerns that the school may have about prolonged use of computers. In each case explain how the school could minimise these risks.	[4]
	Eye strain - - make sure the lighting is not producing glare on the monitor screens. Back or neck strain - - make sure seating arrangements at the workstations are properly set up so users are comfortable and not straining to use the computers.

10.	In the following question, additional credit ( up to 3 marks) will be given if your answer demonstrates skill in written communication. The operating system of a microcomputer has several roles. using examples where appropriate, describe in detail each of the following the typical functions of the operating system from the user's point of view the utilities provided by the operating system the management of resources by the operating system.	[8+3]
	The first task for the operating system when the computer is switched on is to boot up - a small program stored on a ROM chip loads the main parts of the operating system into memory. The operating system also loads and runs any program that the user selects. The program is transferred from backing store, such as a hard drive, and loaded into memory. The place in memory where the program is stored is determined by the operating system. The running of the program is then also started. If there are any errors occurring in the system, the operating system will output a message to the user to indicate what type of error has occurred. There will be a number of utilities provided such as programs to perform every-day tasks such as copying files from one drive to another, formatting a drive, defragmentation or checking a drive for physical damage. These utilities are only loaded into memory when they are needed. The operating system will also make sure that data from all input devices is stored and processed correctly, and that output data is sent to the correct device. Any interrupts received from a device must be serviced by the operating system.