The student clearly stated the independent variable as heating time and the dependent variable as the concentration of Fe2+ ions leached, which was correctly identified in the research question. However, the student did not describe the analytical method used to address the research question, which would improve clarity. The methodology was well-detailed, allowing for reproducibility, and the student effectively identified control, safety, and environmental issues associated with the investigation. While the student addressed the sampling technique and discussed the measurement intervals, they failed to identify any ethical issues, which should have been addressed to enhance the investigation's thoroughness
