Explain why the question T: Type of data€” one variable or two? Categorical or numerical? is one of the four key questions used to guide decisions about what inference method should be considered.
For each of the studies described in Exercises 7.38 to 7.40, answer the following key questions:

Question Ty pe Study Type Ty pe of Data Number of Samples Estimation or hypothesis testing? Sample data or experiment data? One variable or two? Categorical or numerical? How many samples or treatments? or Treatments