Amachine produces metal rods used in an automobile suspension system. a random sample of 15 rods is selected, and the diameter is measured. the resulting data (in millimeters) are as follows: 8.24, 8.25, 8.20, 8.23, 8.24, 8.21, 8.26, 8.26, 8.20, 8.25, 8.23, 8.23, 8.19, 8.33, 8.24. how many more samples do you need to collect to estimate the mean to within 0.005 mm with 95% two-sided confidence? assume degrees of freedom is 14 for the t distribution for calculation of this problem. report your answer as a whole number.