Refer to Commercial properties Problem 6.18. Assume that regression model (6.5) for four predictor variables with independent normal error terms is appropriate. Three properties with the following characteristics did not have any rental information available. 2 3 Xl: 4.0 6.0 12.0 X2: 10.0 11.5 12.5 X3: 0.10 0 0.32 X4: 80,000 120,000 340,000 $. Develop separate prediction intervals for the rental rates of these properties, using a 95 percent statement confidence coefficient in each case. Can the rental rates of theslthree properties be predicted fairly precisely? What is the family confidence level for the set of three predictions?