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 a Length of stay (measured in days), plus b* Presence of one or more complications = 1 if true, O if false), plus c* Use of a laparoscope (= 1 if true, O if false) Where: a, b, c are coefficients of the regression model, and The laparoscope is an instrument somewhat like a miniature telescope with a fiber optic system which brings light into the abdomen. It is about as big around as a fountain pen and twice as long. The research, based on 57 patients, showed the following regression results: R-squared: 53% Constant term: $3,719 Coefficients and t-values for independent variables: . Coefficient t-value Length of Stay Complication Laparoscope $861 $1,986 $908 10.76 4.89 2.54 Required: 1. What is the estimated cost for a patient whose surgery has complications and who stays in the hospital two days, and whose surgery requires a laparoscope? Estimated cost 2. Which, if any, dummy variables are used in this regression? (You may select more than one answer. Click the box with a check mark for the correct answer and click to empty the box for the wrong answer.) Presence of one or more complications Use of a laparoscope (or not) Length of stay (measured in days)