1. Outline 4 functions of a typical operating system of a PC (4)

Resource managementOperating systems organise how to:•Load programs from backing storage devices, •Store them in memory and start them running

Providing an Interface The user interface is the link between the computer and user. It is the job of the operating system to make this as easy as possible. Often these are GUI (Graphical User Interfaces)Good user interfaces are:•Easy to use•Intuitive•Robust ( if correct settings applied)•Consistent

Backing Store / File ManagementOperating systems organise how and where files are located on hard disks./ DVDs / •Often this Is in a hierarchical structure•They also allow attributes to be added e.g. read only

Disk StorageOperating systems are responsible for the efficient running of Disk storage including•Defragmentation of the disk to speed up access times•Compression to save storage space

2. A theatre used a real time transaction processing system to handle its bookingsa) What is meant by a real time transaction system? (2)

b) Explain how this system would operate when a person wishes to book a seat for a performance. (2)

c) Give 2 benefits that this system gives. (2)

An on-line system in which transactions are processed as they occur.In this situation 'Real-time' basically means that if you look at the state of the system at any instant it is up-to-date.

•In these systems a user will choose a seat for a performance•As soon as they ‘takes hold’ of the seat everyone else is ‘locked out’ of that seat and cannot access it to book it.•When the booking has taken place that the seat is immediately removed from the available list in order to another person the same seat, thus giving a double booking.

•No double bookings – explained above•Bookings can be made from anywhere at anytime and get instant confirmation

3 a) Describe what is meant by batch processing. (2)

b) Explain a situation where batch processing could be used. Say why it is suitable. (2)

•Data is gathered together over a period of time. The data is stored in a queue awaiting processing. At the end of the period of time or when a certain amount of data has been collected it is then processed all together as a batch.

•It is said to be a non – interactive process. The user does not get an immediate response from the system.

•Payroll - for a company . All the time-sheet details of the workers for that week (hours worked, overtime etc) are gathered together after the week is over. •The processing can be done overnight as no interaction is needed.

•It is suitable because there is no need for immediate response needed All the system needs to do is meet the deadline set

4. a) What is meant by the term Spooling. Describe how the system might work.(2)

b) What are 2 benefits of spooling (2)

5. Describe and draw the structure and give an example of what is meant by the following termsa) a serial file (2)

b) a sequential file (2)

6. a) Describe using an example how records could be organized usingVariable Length Records (2)

b) What are 2 benefits of variable length records over fixed (2)

7. A particular system uses a sequential approach to storing its recordsa) Outline how the file may be updated with a batch of transactions (4)

b) What back up features would a sequential system have in place (2)

8. a) What is meant by DBMS and describe 2 functions of a DBMS (2)

9. Describe what is meant bya) Validation (2)

b) Verification (2)

11. a) Outline what a check digit is and how a it could be generated (2)

b) Briefly describe 2 other validation checks (2)

12. A garage records all of its bookings for maintenance, services and MOTs in a diary. When a booking is made it is written in the diary. When the work is done the mechanic writes down a list of tasks, parts and time taken on a sheet of paper and places this sheet inside the diary. The owner takes out these sheets on a weekly basis and writes up bills.

a) Describe 2 problems with the current system (4)

b) The owner wants to buy a computer to help. What software would you recommend and why (4)