A normal probability plot of the n = 26 observations on escape time given above shows a substantial linear pattern; the sample mean and sample standard deviation are 371.04 and 24.42, respectively. (Round your answers to two decimal places.)
Required:
a. Calculate the upper confidence bound for a population mean escape time at 95% confidence level assuming the population distribution is normal.
b. Prior to the simulated escape exercise, the investigator believed that true average escape time is at most 360 seconds. Does the data contradict this belief at 95% confidence?