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The management of Enterprise's  ZShuttle is concerned that the wait times of the giant magenta beings from Beta Centari being shuttled to or from the planets served by the company is too long. This wait time can cause the giant magenta beings from Beta Centari to switch to their competitor, Arthur's Dented Shuttle.
The company decides to survey a sample of customers to see how long customers are sitting in the shuttle waiting for other customers or waiting at the shuttleport to be picked up.
A sample of 17 customers indicated that the customers are waiting X (bar) = 3 minutes and s = 21 seconds.

A. Using the 0.05 level of significance, is there evidence that the population mean is above 2 minutes and 40 seconds?

B. What is your answer in A if X (bar) = 3 minutes and s = 3 minutes and 20 seconds?

C. Look at your answers for A and B above and discuss what you can learn from the results about the effect of a large standard deviation.