1.Dr. Ahmed teaches organic chemistry. She is studying whether posting a review video will affect students' final exam grades. She knows that at the college, the final exam mean is = 72 (x = 9.22). She drew a sample of 15 students and gave them a link to a video review. (She built in a manipulation check to ensure that all students did watch the video.) She found that their final exam mean was 77. a. What is the null hypothesis? What is the research hypothesis? b. If what is the critical value? c. Analyze the data, using the appropriate statistical test. d. How should she interpret the results? e. If applicable, compute the 95% confidence interval around the mean. Explain this. f. If applicable, compute the effect size. Explain this.