Bluff Meats Butchery supplies vienna sausages in the entire of KZN province. An Inspector from the CCSA has been sceptical of the mass of the Vienna sausage packs after receiving numerous complaints. He wants to investigate the marked mass shown on Vienna sausages. A pilot study showed a mean of 11.8kg per pack and a standard deviation of 0.7kg. How many packs should be sampled by the Inspector in order to be 98% confident that the sample mean will differ by at most 0.2kg?