Two machines are used for filling glass bottles with a soft-drink beverage. the filling processes have known standard deviations liter and liter, respectively. a random sample of bottles from machine 1 and bottles from machine 2 results in average net contents of liters and liters. (a) test the hypothesis that both machines fill to the same net contents, using what are your conclusions? (b) find the p-value for this test. (c) construct a 95% confidence interval on the difference in mean fill volume.