1. The use of cellular phones has been associated with the development of brain cancer, as evidenced in several studies. However, other studies have shown no such association. The table below includes the results of a case-control study of brain tumors and the regular use of cellular phones. This study was conducted using a control group made up of a random sample of the population of high school students who attended the same schools where the students with brain tumors were found.

	I	Brain Tumors	No Brain Tumors
Cell Phones	63	85
No Cell Phones	96	292

1. How many study subjects were cases?
2. How many study subjects were controls?
3. What was the ratio of controls to cases?
4. Calculate the odds ratio that compares exposure to cellular phones among those with and without the disease.
5. Make a conclusion based on the calculated odds ratio