The following are airborne times (in minutes) for 10 randomly selected flights from San Francisco to Washington Dulles airport.

271

257

268

286

274

275

266

258

271

281

(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.We are 90% confident that the true mean airborne time for flights from Washington Dulles to San Francisco is between these two values. 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.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.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.(b)Give an interpretation of the 90% confidence level associated with the interval estimate in part (a).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.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. 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.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 90, 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.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.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 1:50 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 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 2:50 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.