my research question is why do some rich countries have strict air pollution than others ?

my hypothesis is that rich countries have more environmental law

units are the countries the i am going to comapre china as a poor country , japan as a rich country , and find middle class country .

my independent variable( is how rich is the country )

the depandant varible is how small is the environmental laws

write a case study about japan

measure the dependent variable and the independent variable about this case and explain why is it appropriate.

instruction what the professor said :

• State your hypothesis and define your key variables. Include a draft of a case study of one of your observations. (For one of the cases you will use in the term paper, explain how you observe the independent and dependent variable. The case study must include a specific description of the variables and an explanation of how you operationalize them.)
• Minimum 3 pages, and at least 4 references on the content of the case (that is, at least 4 different sources that provide specific information that you used for evidence about the case; these do not need to be scholarly articles).
• Suggested format:
  • Statement of hypothesis (about 1 short paragraph)
  • Description of at least one independent variable (about 1 paragraph)
  • Description of dependent variable (about 1 paragraph)
  • Introduction of case study (about 1 paragraph)
  • Measurement of the value of at least one independent variable in that case study (about 1-3 paragraphs)
  • Measurement of the value of the dependent variable in that case study (about 1-3 paragraphs)