(a) A shop in downtown Perth is considering moving from its present location to Fremantle. One factor in this decision is the amount of time the shop's employees spend travelling to work. A random sample of 20 employees, at the current site, reveals that the mean and standard deviation of the time required to get to work are 36.5 and 11.8 minutes, respectively. Estimate the 95% confidence interval of the mean time to get to work.