The student uses correct mathematical notation, symbols, and terminology consistently throughout the IA, accurately expressing the exponential and logistic growth models with appropriate definitions. The inclusion of Python code in the appendix demonstrates the application of software-generated notation and effectively showcases the implementation of various models. Key terms and variables are defined and explained upon their introduction, and the main concepts are clearly described in the introduction, with a focus on mobile phone adoption and the analysis of historical data. The student employs multiple forms of mathematical representation and provides thorough explanations of all calculations, although there are areas where the degree of accuracy for rounded values is not stated, and results are not rounded only at the end of the calculation thread. Overall, the student effectively uses a deductive method, with well-labelled graphs, tables, and diagrams enhancing the clarity of the investigation.
