A car company wants to know the monthly sales made in ($000), based on the brand of vehicle. The data collected was entered on a MINITAB spreadsheet for analysis. Exhibit II below was subsequently...

A car company wants to know the monthly sales made in ($000), based on the brand of vehicle. The data collected was entered on a MINITAB spreadsheet for analysis. Exhibit II below was subsequently generated.

model            N        MEAN      MEDIAN  TRI. MEAN     STD DEV    SE MEAN

hyumdai         23         109          135            107.64                *             1.34

toyota             27         165          124            143.65              9.5             **

d) Assuming normality, construct and interpret a 90% confidence interval for the average monthly earning from Toyota Vehicles.
e) You are required to test at the 5% level of significance the hypothesis that the average monthly earnings on Hyundai Vehicles is equal to $110,000 versus the alternative that it is different from $110,000.