The following are airborne times (in minutes) for 10 randomly selected flights from San Francisco to Washington Dulles airport. 269 257 266 286 274 275 266 258 271 281 LA USE SALT (a) Calculate a 90% confidence interval for the mean airborne time for flights from San Francisco to Washington Dulles. (Round your answers to three decimal places.) Interpret a 90% confidence interval for the mean airborne time for flights from San Francisco to Washington Dulles. . We are 90% confident that the mean airborne time for flights from San Francisco to Washington Dulles is between these two values. O We are 90% confident that the true mean airborne time for flights from Washington Dulles to San Francisco is between these two values. O We are 90% confident that the true mean airborne time for flights from San Francisco to Washington Dulles is directly in the middle of these two values. O There is a 90% chance that the true difference in the mean airborne time for flights from San Francisco to Washington Dulles is directly in the middle of these two values. O There is a 90% chance that the true mean airborne time for flights from Washington Dulles to San Francisco is directly in the middle of these two values. (b) Give an interpretation of the 90% confidence level associated with the interval estimate in part (a). O If we were to take a large number of random samples of size 10, 95% of the resulting confidence intervals would contain the true mean airborne time. If we were to take a large number of random samples of size 10, 90% of the resulting confidence intervals would contain the true mean airborne time. O If we were to take a large number of random samples of size 90, 10% of the resulting confidence intervals would contain the true mean airborne time. If we were to take a 10 random samples of size 10, 10% of the resulting confidence intervals would contain the true mean airborne time. O If we were to take a large number of random samples of size 10, 10% of the resulting confidence intervals would contain the true mean airborne time. (c) If a flight from San Francisco to Washington Dulles Is scheduled to depart at 10 A.M., what would you recommend for the published arrival time? Explain. O We would recommend 4:50 P.M., assuming normality and that this sample is representative of the population. We can assume that approximately 5% of flights will arrive after this time. We would recommend 3:50 P.M., assuming normality and that this sample is representative of the population. We can assume that approximately 5% of flights will arrive after this time. We would recommend 2:50 P.M., assuming normality and that this sample is representative of the population. We can assume that approximately 95% of flights will arrive after this time
