The QC supervisor at National Bakery has been asked to direct the receipt inspection of a carload shipment of flour. Each bag is supposed to weigh at least 50 kg and the Chicago Mill hassaid the standard deviation is 4 kg. Management wishes to limit the risk of rejecting a good lot to 2 percent. On the other hand, if the true mean weight of the bags is only 48 kg, they desire to limit the chance of accepting the shipment to 5 percent.

a) How large a sample sizen is required ?