2) A researcher is interested in a drug to treat depression. A sample of n = 16 individuals is selected from a population with u = 30 on a self-reported measure of happiness. After the drug is administered to the individuals, the sample mean is found to be M = 33 and the sample variance is found to be s2 = 64. a. Is there is significant difference between the population and the sample on self-reported happiness? Conduct a hypothesis test to answer this question. b. Interpret the results of the hypothesis test. c. Compute Cohen's d. What does it say' about the size of the effect? d. Compute r2. What does it say about the size of the effect? e. Compute the 95% confidence interval. What does the confidence interval mean