A vitamin K shot is given to infants soon after birth. Nurses at Northbay Healthcare were involved in a study to see if how they handle the infants could reduce the pain the infants feel("SOCR data nips, "2013). One of the measurements taken was how long, in seconds, the infant cried after being given the shot. A random sample was taken from the group that was given the shot using conventional methods, and a random sample was taken from the group that was given the shot where the mother held the infant prior to and during the shot. The sample from the group using conventional methods had a mean of 35.3 seconds with a standard deviation of 20.8 seconds. The sample from the group where the mother held the infant had a mean of 35.1 seconds and a standard deviation of 22.3 seconds. Both had sample sizes of 30. Calculate a 99% confidence interval for the mean difference in mean crying time after being given a vitamin K shot between infants held using conventional methods and infants held by their mothers.