A quality control inspector samples 20 nails from a machine, and for the sample, calculates the average length as 0.96, and standard deviation as 0.02. The machine is set to produce nails which are 1 inch long. The population of the lengths is assumed to be normally distributed. Use a significance level of 5%.... the question then asks to do the two tail, upper tail, and lower tail test. I know the test statistic is -8.94 for all of them, and i know the critical value for each (2.093,1.729,and -1.729). how do you find the p value for each test?