A researcher conducted an experiment and measured the amount of dopamine in the brains of monkeys receiving SSRIs and in control animals.

1. Please list the variables and if each one is Numerical or categorical.
2. Please list if each variable is explanatory, response or unknown.
3. Which graph would you use to visually depict this data?
4. Please write which hypothesis test is used to analyze the data, and list the null and alternative hypothesis to test the relationship.
5. Identify which table you would use to calculate a p-value for the test you performed
6. Should this p-value should be left alone, doubled or halved?