1. A clinical psychologist wants to investigate whether patients who have suffered childhood abuse have a lower level of self-efficacy as adults compared to the general population of US adults. Assume scores on the self-efficacy questionnaire (SEQ) for the general population of US adults are distributed normally with a mean of 48.2. A sample of 28 US adults who suffered childhood abuse has a mean score on the SEQ of 49.6 and a standard deviation of 5.3. The significance level for the test is equal to 0.01. What is the value of the effect size? Give value to the nearest three decimals.

2. A student is studying happiness and wants to test the mean score of her sample against the population mean. She calculates 85% Confidence Interval [2.26, 4.72] and concludes that there is an 85% chance the true population mean is contained within this interval. What can you say about this interpretation? a. there is nothing wrong. b. it is fine, but 85% is usually too small of a confidence interval to use. c. not the correct interpretation of confidence intervals. d. there is a significant difference in happiness scores based on the confidence interval provided.