1. Scott is the owner of a tool and die shop. He has hired you to check his machine's calibration prior to starting production on a large order. To check this, you set the machine to create 1.5 inch screws and manufacture a random sample of 200 screws. That sample of screws has an average length of 1.476 inches with a standard deviation of 0.203 inches.

Does this sample provide convincing evidence that the machine is working properly or should it be shut down for repairs?

2. In a study of the performance of a new engine design, the weight of 22 aircrafts (in tons) and the top speed (in mph) were recorded. A regression line was generated and shown to be an appropriate description of the relationship. The results of the regression analysis are below.

Number of Courses| Employment Status| Total Job No Job Four 19 30 49 Three 27 25 52 TWO 37 12 49 Total 83 67 150Depend Variable: Top Speed Variable Coefficient s.e. of Coeff t-ratio prob Constant 11.6559 0.3153 37 $ 0.0001 Weight 3.47812 0.294 11.8 $ 0.0001 R squared = 87.5% R squared (adjusted) = 86.9% 5 = 0.6174 with 22 - 2 = 20 degrees of freedom