11. A manager is planning to take a sample to determine the average distance (km) that repair technicians travel in a day. They would like to use a 95% confidence level, and will assume a population standard deviation of = 19.2876 km, based on past studies. What size of sample is required in order to ensure that the margin of error () is not more than 10.0 km? (Round answer to whole number - note that it is not necessarily the closest whole number, think about how this answer should be rounded).