The student clearly stated the independent and dependent variables in the research question, identifying household chemicals as the independent variable and the change in stain intensity as the dependent variable. The method of analysis was also described, detailing how the effect of these chemicals on stain removal would be measured using a Vernier light sensor. While the student provided a thorough background theory relevant to the investigation, a clear explanation of the measurement techniques for both variables was lacking. However, the student effectively discussed the sampling techniques, controlled variables, safety, ethical, and environmental considerations, demonstrating a comprehensive understanding of the experimental design and methodology, which was described sufficiently for reproducibility without irrelevant information.
