A study of the effects of smoking on sleep patterns is conducted. The measure observed is the time, in minutes, that it takes to fall asleep. These data are obtained: Smokers: 69.3 56.0 22.1 47.6 53.2 48.1 52.7 34.4 60.2 43.8 23.2 13.8 Nonsmokers: 28.6 25.1 26.4 34.9 29.8 28.4 38.5 30.2 30.6 31.8 41.6 21.1 36.0 37.9 13.9 (a) Find the sample mean for each group. (b) Find the sample standard deviation for each group.

Using the computer output, what is the predicted foot length for a student with an arm span of 160 cm? The arm span and foot length were measured (in centimeters) for each of the 19 students in a statistics class and displayed in the scatterplot. An analysis was completed and the computer output is shown. 5.79 cm 22.15 cm O29.76 cm Arm Span vs. Foot Length O29.80 cm 29 27 25 23 21 19 155 160 165 170 175 180 185 190 195 Foot Length (cm)

The height (in feet) and trunk circumference (in inches) at breast height (4.5 feet above the ground)was measured for a random sample of Eucalyptus trees. The data are summarized below.Trunk Circumference 21.1 20.8 22.5 19.4 23.6 19.8 21.6 19.9Tree Height 34.2 32.7 35.0 31.9 36.5 31.2 33.8 31.4(a) Determine the linear regression model that will best predict the height of a Eucalyptus treebased on its trunk circumference at breast height.

The data below represent the number of days absent, x, and the final grade, y, for a sample of college students at a large university. Complete parts (a) through (e) below. У, No. of absences, x 1 2 4 6. 7 8 9. Final grade, y 88.8 85.9 83.0 80.6 77.7 73.3 63.5 68.3 65.4 62.6 (Round to three decimal places as needed.) A. For every unit change in the final grade, the number of days absent falls by days, on average. B. For every day absent, the final grade falls by on average. C. For zero days absent, the final score is predicted to be 88.778 . D. For a final score of zero, the number of days absent is predicted to be days. E. It is not appropriate to interpret the y-intercept. (c) Predict the final grade for a student who misses five class periods and compute the residual. Is the observed final grade above or below average for this number of absences? The predicted final grade is |. This observation has a residual of, which indicates that the final grade is average. (Round to one decimal…