questions 1-3
A medical researcher is investigating the effect of drinking coffee on Select one answer. systolic blood pressure. The researcher assumes the average systolic 10 points blood pressure is 120 mmHg. For a random sample of 200 patients, the researcher takes two measurements of systolic blood pressure. The rst systolic blood pressure measurement is taken during a week when the patients drink no coffee, and the second systolic blood pressure measurement is taken during aweek when the patients drink at least two cups of coffee. The medical researcher wonders whether there is a signicant difference between the blood pressure measurements. Which of the following is the correct null and alternative hypothesis for the medical researcher's study? A. -H0:p:120;Ha:p12o B. -H0:p=o;Ha:po C. -H0:p:o;Ha:p12o Question 2 In a ctional study, suppose that a psychologist is studying the effect Select one answer. of daily meditation on resting heart rate. The psychologist believes 10 points the patients who not meditate have a higher resting heart rate. For a random sample of 45 pairs of identical twins, the psychologist randomly assigns one twin to one of two treatments. One twin in each pair meditates daily for one week, while the other twin does not meditate. At the end of the week, the psychologist measures the resting heart rate of each twin. Assume the mean resting heart rate is 80 heart beats per minute. The psychologist conducts a T-test for the mean of the differences in resting heart rate of patients who do not meditate minus resting heart rate of patients who do meditate. Which of the following is the correct null and alternative hypothesis for the psychologist's study? A. -H0:p=80;Ha:p>Bo B. - Hozu:o;Ha:po C. -H0:p:o;Ha:p>o Question 3 An urban planner is researching commute times in the San Francisco Select all that Bay Area to nd out if commute times have increased. In which of apply. the following situations could the urban planner use a hypothesis test 10 points for a population mean? Check all that apply. A. H The urban planner asks a simple random sample of 110 commuters in the San Francisco Bay Area if they believe their commute time has increased in the past year. The urban planner will compute the proportion of commuters who believe their commute time has increased in the past year. B. H The urban planner collects travel times from a random sample of 125 commuters in the San Francisco Bay Area. A trafc study from last year claimed that the average commute time in the San Francisco Bay Area is 45 minutes. The urban planner will see if there is evidence the average commute time is greater than 45 minutes. C. H The urban planner asks a random sample of 100 commuters in the San Francisco Bay Area to record travel times on a Tuesday morning. One year later, the urban planner asks the same loo commuters to record travel times on a Tuesday morning. The urban planner will see if the difference in commute times shows an increase
