Прочитайте текст и заполните пропуски (1-10) частями предложений, обозначеннымибуквами A - K. Одна из частей в списке A – K лишняя.A – An operating system is stored on a diskB – A computer solves problemsC – which controls the functions of the computer system as a wholeD – other users are denied accessE – as the development costs are spread over a greater number of users, both actual and potential.F – to deal with real-time enquiries or file updatesG – as only one user can access the system at any moment of timeH – whilst the ‘foreground’ job deals with real-time operationsI – other modules being read in from disk as requiredJ– After the real-time operation has been dealt withK – while the processor is performing computations on another1. An operating system is a master control program other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time ______ and the running of application programs. All computers do not use the same operating systems. It is therefore important to assess the operating system used on a particular model before initial commitment because some software is only designed to run under the control of specific operating systems. Some operating systems are adopted as ‘industry standards’ and these are the ones which should be evaluated because they normally have a good software base. The reason for this is that software houses are willing to expand resources on the development of application packages for machines functioning under the control of an operating system which is widely used. The cost of software is likely to be lower in such circumstances other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______.2. Mainframe computers usually process several application programs concurrently, switching from one to the other, for the purpose of increasing processing productivity. This is known as multiprogramming (multi-tasking in the context of microcomputers), which requires a powerful operating system incorporating work scheduling facilities to control the switching between programs. This entails reading in data for one program other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______ and printing out the results on yet another.3. In multi-user environments an operating system is required to control terminal operations on a shared access basis other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______. The operating system allocates control to each terminal in turn. Such systems also require a system for record locking and unlocking, to prevent one user attempting to read a record whilst another user is updating it, for instance. The first user is allocated control to write to a record (or file in some instances) and other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______ until the record is updated or unlocked.4. Some environments operate in concurrent batch and real-time mode. This means that a ‘background’ job deals with routine batch processing other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______ such as airline seat reservation, on-line booking of hotel accommodation, or control of warehouse stocks, etc. The real-time operation has priority, and the operating system interrupts batch processing operations other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______. The stage of batch processing attained at the time of the interrupt is temporarily transferred to backing storage. other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______, the interrupted program is transferred back to internal memory from backing storage, and processing recommences from a ‘restart’ point. The operating system also copies to disk backing storage the state of the real-time system every few minutes (periodic check points) to provide a means of ‘recovering’ the system in the event of a malfunction.5. other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______ and has to be booted into the internal memory (RAM) where it must reside throughout processing so that commands are instantly available. The operating system commands may exceed the internal memory capacity of the computer in which case only that portion of the OS which is frequently used is retained internally, other modules being read in from disk as requiredAfter the real-time operation has been dealt withAn operating system is stored on a diskwhich controls the functions of the computer system as a wholeas the development costs are spread over a greater number of users, both actual and potential.to deal with real-time enquiries or file updateswhilst the ‘foreground’ job deals with real-time operationsother users are denied accesswhile the processor is performing computations on anotheras only one user can access the system at any moment of time _______. Many microcomputers function under the control of a disk operating system known as DOS.