The student clearly states the independent variable as the source of catalase (chicken liver and cow liver) and the dependent variable as the activation energy for the decomposition of hydrogen peroxide. The research question effectively outlines the method of analysis, involving the measurement of oxygen gas production at different temperatures. The background theory is well-developed, connecting relevant concepts to the investigation, and the choice of techniques for measuring the variables is thoroughly explained. The student also discusses the sampling technique, controlled variables, and addresses safety, ethical, and environmental issues associated with the investigation. However, the methodology lacks sufficient detail in describing how the target temperature was achieved, which may hinder reproducibility. Overall, the methodology is presented clearly without irrelevant or repetitive information.
