Test whether revenue and advertising expenditures are related at a .05 level of significance. Answer + Prepare a residual plot of y – ŷ versus ŷ. Use the result from part (a) to obtain the values of ŷ. Answer + What conclusions can you draw from residual analysis? Should this model be used, or should we look for a better one?

Challenge The following box plots show monthly average high temperature from January to December in degrees Fahrenheit for two U.S. cities. Which city should you live in if you want the most variability in temperature? City X City Y 10 15 20 25 40 45 50 55 60 10 15 20 25 30 35 40 45 50 55 60 Degrees Fahrenheit Degrees Fahrenheit Which city should you live in if you want the most variability in temperature? O A. City X and City Y, because they have the same variability in te O B. City Y OC. City X

DATA file Autoinsurance 20. Assignment 3 The average annual premium for automobile insurance in the United States is $1503 (Insure.com website, March 6, 2014). The following annual premiums ($) are representa- tive of the website's findings for the state of Michigan. 1905 2725 2677 2600 2962 2184 2332 3112 2545 2525 2370 2545 2529 2442 2312 2981 2627 2857 2675 2115 Assume the population is approximately normal. a. Provide a point estimate of the mean annual automobile insurance premium in Michigan. b. Develop a 95% confidence interval for the mean annual automobile insurance pre- mium in Michigan. C. Does the 95% confidence interval for the annual automobile insurance premium in Michigan include the national average for the United States? What is your interpreta- tion of the relationship between auto insurance premiums in Michigan and the national average?

Quiz Module 1 The stem-and-leaf plot shows house sale prices over the last week in Tacoma. The stem is in hundres of thousands of dollars the leaf is in tens of thousands of dollars. What is the price of the most expensive house sold? 0|6677789991|024477788899992|00112344456678893|00011224