A researcher is interested in the effects of diazepam on anxiety in rats. She takes a group of 15 female rats and injects them with 0.005 mg of diazepam for every 100 g the rats weigh, and takes a different group of female rats and injects them with saline. She then puts them all on an elevated-plus maze for 15 minutes and observes how long they spend (in seconds) in the enclosed arms versus the open arms. The less time they spend in the enclosed arms means they have less anxiety. She also weighs them before the injection to make sure she gets the dosage correct. a. Identify the population of interest b. Identify the Independent variable. c. Identify the Dependent variable. od for the indenendent variable? Explain why

We want to know if students with bronchitis at 5 years have more cough symptoms when they grow up. Out of 290 children with Bronchitis at Age 5, 32 of them has cough symptoms at Age 12. Out of 970 children with no Bronchitis at Age 5, 43 of them has cough symptoms at Age 12. Is the cough symptom equally prevalent in both populations?

A researcher wonders if there an association between the incidence of colds and the amount of Vitamin C taken. He recruits 93 volunteers and randomly assigns 26 of them to take 500 mg of Vitamin C, 18 of them to take 1000 mg of Vitamin C and the rest to take no Vitamin C. At the end of the study, it was determined that 30 of the volunteers did not have any colds where 15 of them were in the 500 mg group, 11 of them were in the 1000 mg group, and the rest took no Vitamin C. Test the appropriate hypothesis at a = 0.01. Round your answers to three decimal places, if necessary. Fill in the hypotheses below: Ho: There is not vitamin C taken. Ha: There is vitamin C taken. Complete the table of expected counts under the null hypothesis: No Vitamin C 500mg Vitamin C 1000mg Vitamin C an association between the incidence of colds and the amount of an association between the incidence of colds and the amount of At least one cold 17.613 12.194 No colds 15.806 12.194 Part 2 of 5

A researcher wonders if there an association between the incidence of colds and the amount of Vitamin C taken. He recruits 93 volunteers and randomly assigns 26 of them to take 500 mg of Vitamin C, 18 of them to take 1000 mg of Vitamin C and the rest to take no Vitamin C. At the end of the study, it was determined that 30 of the volunteers did not have any colds where 15 of them were in the 500 mg group, 11 of them were in the 1000 mg group, and the rest took no Vitamin C. Test the appropriate hypothesis at a = 0.01. Round your answers to three decimal places, if necessary. Fill in the hypotheses below: Ho: There is not vitamin C taken. Ha: There is vitamin C taken. Complete the table of expected counts under the null hypothesis: No Vitamin C 500mg Vitamin C 1000mg Vitamin C No Vitamin C 500mg Vitamin C 1000mg Vitamin C At least one cold 33.194 an association between the incidence of colds and the amount of an association between the incidence of colds and the amount of 17.613 12.194…