A random sample of 12 subjects was asked to perform a given task. The time in seconds it took each of them to complete the task is recorded below. 31, 44, 50, 25, 28, 44, 33, 50, 50, 49, 33, 39 Send data to calculator If we assume that the completion times are normally distributed, find a 90% confidence interval for the true mean completion time for this task. Then find the lower limit and upper limit of the 90% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit: X 5 ? Upper limit