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Exercise 8-39 Interpreting Regression Results [LO 8-3) Recent research into the cost of various medical procedures has shown the impact of certain complications encountered in surgery on the total cost of a patient's stay in the hospital. The researchers used regression analysis and found the following results: Total cost for patient = Constant, plus ax Length of stay (measured in days), plus b* Presence of one or more complications (+11f true, o if false), plus c* Use of a laparoscope (= 1 if true, o if false) where a, b, care coefficients of the regression model. The laparoscope is an instrument somewhat like a miniature telescope with a fiber optic system that brings light into the abdomen. It is about as big around as a fountain pen and twice as long. The research, based on 71 patients, showed the following regression results: R-squared: 51% Constant term: $3,929 Coefficients and e-values for independent variables: Length of Stay Complications Laparoscope Coefficient $1,995 t-value 9.48 5.84 $ 780 $ 949 2.24 Required: 1. What is the estimated cost for a patient whose surgery has complications and who stays in the hospital 5 days, and whose surgery requires a laparoscope? Estimated cost Exercise 8-33 Cost Estimation Using High-Low; Graphs (LO 8-3] Lawson Advertising Agency is trying to persuade Kansas City Sailboards Company to spend more on advertising. The agency's argument is that a constant and strong positive relationship exists between advertising and sales in the sailboard industry. Sue Lawson presents these data taken from industry data for stores similar in size and market share to Kansas City Sallboards: Advertising Expense Annual Sales $2,500 $ 96,000 3,000 110,000 3,500 124,000 4.000 138,000 4,500 143,000 5.000 147.000 5,500 150,000 Required: 1. Use the high-low method to estimate the relationship between increased advertising and sales, Amount of increased sales for every dollar of advertising Exercise 8-32 Cost Estimation; Average Cost [LO 8-2] Chloe's Cafe bakes croissants that it sells to local restaurants and grocery stores. The average costs to bake the croissants are $0.55 for 3.600 and $0.50 for 7.200, Required: If the total cost function for croissants is linear, what will be the average cost to bake 6,400? (Do not round intermediate calculations, Round your final answer to 4 decimal places.) Average cost