It is recommended that three-year old children should spend an average of 12 hours a day sleeping. A survey was done at KinderCare in Walnut and 22 parents who had a 3-year old were surveyed. They were asked to disclose how many hours a night that their three-year old slept. The mean hours they slept was 13 hours and a standard deviation of 2.5 hours. Use the Empirical Rule to answer the following questions