Construct the empirical cumulative distribution function for the data set of paint thicknesses given in DS 6.1.8. Draw 95% confidence bands around the empirical cumulative distribution function. Analyze the median (or mean) paint thickness using the sign lest, the signed rank test, and the t-test. Pay particular attention to whether the median paint thickness is 0.2 mm. Which analysis method do you prefer? Summarize your conclusions.