GCSE COMPUTER SCIENCE 8525 QUESTION AND ANSWER (Paper 1 Computational thinking and programming skills – C#)

GCSE COMPUTER SCIENCE 8525 QUESTION AND ANSWER (Paper 1 Computational thinking and programming skills – C#) Waterfall Model (Definition, Advantages and Disadvantages) - ANSWER Each process takes place, from top to bottom, to completion before the next process begins. + It is easy to manage, as the whole process is readily divisible into smaller processes. + It is easily understood and used. - Unsuitable for larger projects or projects with changing requirements. - Not all projects can be so easily broken down into processes like this, some processes may overlap. Spiral Model (Definition, Advantages and Disadvantages) - ANSWER Similar to the cyclical mode, except each process is visited multiple times in that sequence. Each time a process occurs, it occurs in a more developed way than the last time it occurred. + Good approach for larger projects, as changes can be implemented throughout the project. + A working prototype can be made available fairly early. - Each spiral model approach will be different, meaning less reusability. - Not appropriate for smaller projects where multiple passes may be unnecessary. Feasibility Study - ANSWER The main purpose of this is to examine an existing system to find out whether or not it is worthwhile replacing it with a different system. Replacing a system has certain costs: Money for software developers, hardware etc. Time, designing and installing the new system is time consuming. Human resources, specialist staff are needed to design and install the system and existing staff would need to be retrained to operate it. Benefits of replacing a system: May be possible to do a job faster. May be cheaper to operate, requiring less staff