business statistics

. One measure of physical fitness is how quick the heart rate retums to normal after exercise. There are currently 260 players in the NHL. A random sample of 120 of the players showed that the average time required for their heart rates return to normal was 5.5 minutes with a standard deviation of 2.3 minutes. Construct the 99% confident interval for the true mean time that an NHL player requires to have their heart rate return to normal. (10 marks)