The production manager of Tea Cup Manufacturing (TCM) must determine which of two production methods, BEN and ZEN, maximizes the hourly yields for tea cup production. In order to compute the mean hourly yields obtained by using the two methods, the manager runs the production process using each method for several hourly periods. The resulting yields (in kilograms of cups per hourly period) are shown in the following table. Method BEN ZEN Mean 811 750 Median 775 804 Standard Deviation 19 22 Number of production runs 15 15 (a) The production manager claims that the methods, BEN and ZEN, produce yields with the same amount of consistency. Is there enough evidence to support the manager's claim? Assume the level of significance is 2%. method. (b) Estimate with 99% confidence the consistency of the hourly yields processed using the BEN