Dairy cows at large commercial farms often receive injections of bST (Bovine Somatotropin), a hormone used to spur milk production. Bauman et al. (Journal of Dairy Science, 1989) reported that 12 cows given bST produced an average of 28.0 kg/d of milk. Assume that the standard deviation of milk production is 2.25 kg/d and the distribution is normal. (a) Find a 99% confidence interval for the true mean milk production. (b) If the farms want the confidence interval to be no wider than 2.5 kg/d, how many cows should they include in the study

Amanufacturing firm has been averaging 16.8 orders per week for several years. however, during a recession, orders appeared to slow. suppose the firm’s production manager randomly samples 31 weeks and finds an average of 15.6 orders with a standard deviation of 2.3 orders. using a 0.025 significance level, test whether the mean number of orders has decreased. type the full 5 step procedure into the answer box, then for multiple choice practice, answer the following: 1. what is the name and symbol of the parameter that you are testing? 2. what is the symbol and value of the point estimate of that parameter? 3. what distribution are you using to test this parameter? 4. what is the critical value? 5. what is the test statistic value? 6. what is the p-value?