1. When to use t-tests and when to use ANOVA? What are the requirements of independent variables and dependent variables (consider the level of measurement for the variables)
2. What are different types of t-test?
3. t-test is often used in intervention studies to evaluate intervention effects.
   1. Develop a research question in your interested area that can be analyzed by using t-test.
   2. What is independent variable, and what is dependent variable in your research question?
   3. Identify the level of measurement for both of your independent variable and dependent variable.
   4. What is your research hypothesis in your example?
   5. Which type of t-test you would use for the data analysis and why?