Please help me with following question.

A company that leases trucks to other companies collected information on total miles driven (100,000 miles) and total maintenance cost (in thousand dollars) for each of 10 trucks in their rental fleet. The company is interested in modeling the relationship between total maintenance cost and total miles of operation so it can more accurately establish mileage charges for leasing these trucks. The analysis is done by SPSS. The output is provided below.

a.) The company wants to estimate the average maintenance cost for trucks driven 300,000 miles and 500,000 miles. One can use either Bonferroni method or Working- Hotelling method to construct the intervals at 90% family confidence level. Find the critical value for each procedure. Which procedure will you recommend? Briefly explain. (You do not have to compute the actual interval.)

b) Comment on the residual plot and suggest a remedial measure if needed.

ANOVA df F 349.417 Mean Square 904.257 2.588 Sig. .000 1 Sum of Model Squares 1 Regression 904.257 Residual 20.703 Total 924.960 a. Predictors: (Constant), MILES b. Dependent Variable: COST 8 9 Coefficientsa Standardized Coefficients Beta t Unstandardized Coefficients Model B Std. Error 1 (Constant) -2.702 .959 MILES 4.751 .254 a. Dependent Variable: COST -2.817 18.693 Sig. .023 .000 .989 Residual plot Unstandardized Residual MILES NI 00 ANOVA df F 349.417 Mean Square 904.257 2.588 Sig. .000 1 Sum of Model Squares 1 Regression 904.257 Residual 20.703 Total 924.960 a. Predictors: (Constant), MILES b. Dependent Variable: COST 8 9 Coefficientsa Standardized Coefficients Beta t Unstandardized Coefficients Model B Std. Error 1 (Constant) -2.702 .959 MILES 4.751 .254 a. Dependent Variable: COST -2.817 18.693 Sig. .023 .000 .989 Residual plot Unstandardized Residual MILES NI 00