Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to estimate its average number of unoccupied seats per flight over the past year. To accomplish this, the records of 250 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.2 seats and the sample standard deviation is 4.1 seats. NOTE: If you are using a Student's tdistribution, you may assume that the underlying population is normally distributed. (In general, you must first prove that assumption, though.) Construct a 92% confidence interval for the population average number of unoccupied seats per flight. (i) State the confidence interval. (Round your answers to two decimal places.) (:ll:l) (ii) Sketch the graph. %= Cl c_L_=:i 522:1 :1 :1 (iii) Calculate the error bound. (Round your answer to two decimal places.) :l kl