b) (4 marks) To study adolescent depression, a random sample of 800 children selected from city high schools was given a questionnaire. Variables measured were: stress, comfort in social situations, attitudes towards parents, social support from parents, socioeconomic status, and level of depression. All variables are measurement scale. A regression analysis was carried out using depression as the dependent variable, and all the others as independent variables. The overall F-test was significant (P