The student clearly stated the independent and dependent variables in the research question, identifying the source of water samples as the independent variable and the presence of water hardness as the dependent variable. The methodology was well described, including the method of analysis using EDTA complexometric titration, and the background theory was relevant and supported by credible sources. The student provided a thorough explanation of the techniques used for measuring variables and effectively discussed controlled variables, safety, ethical, and environmental considerations. However, there was a lack of clarity regarding the sampling technique used, which would enhance the rigor of the methodology. Overall, the student presented a coherent and reproducible method, free from irrelevant or repetitive information.
