An article in knee surgery sports traumatology, arthroscopy, "effect of provider volume on resource utilization for surgical procedures," (2005, vol. 13, pp. 273–279) showed a mean time of 111 minutes and a standard deviation of 16 minutes for acl reconstruction surgery for high-volume hospitals (with more than 300 such surgeries per year).
a. if a high-volume hospital needs to schedule 10 surgeries, what is the mean and variance of the total time to complete these surgeries? assume the times of the surgeries are independent and normally distributed. mean = ? minutes and variance = ?