Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to estimate its mean number of unoccupied seats per flight over the past year. To accomplish this, the records of 225 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.6 seats and the sample standard deviation is 4.1 seats. Construct a 95% confidence interval for the population mean number of unoccupied seats per flight. Round to two decimal places. 95% CI = ( Which distribution do you use when the standard deviation is not known and you are testing one population mean? Assume sample size is large. O Population distribution O Student's t-distribution O Normal distribution O Confidence Interval