Princess Cruises recently offered a 16-day voyage from Beijing to Bangkok during the time period from May to August. The announced price, excluding airfare, for a room with an ocean view or a balcony was listed as $3,475. Cruise fares usually are quite variable due to discounting by the cruise line and travel agents. A sample of 20 passengers who purchased this cruise paid the following amounts (in dollars):

a. Calculate the sample mean cruise fare.
b. Determine the sampling error for this sample.
c. Would the results obtained in part b indicate that the average cruise fare during this period for this cruise is different from the listed price? Explain your answer from a statistical point of view.