Consumers preferences for Western Star butter were obtained on a 7-point Likert scale. The same consumers were then shown a commercial about the brand. After the commercial, preferences were again measured. The question is: "Has the commercial affected consumers' preferences toward Western Star butter".

1. List all variables that are needed to answer this RQ.

2. State the null and alternative hypothesis.

3. Indicate the statistical analysis you would conduct and appropriate test statistics that should be used.