You may need to use the appropriate appendix table or technology to answer this question. A regional airline serving Las Vegas has a base airfare rate of $119. In addition, various fees are charged: for checked baggage, refreshments/drinks in-flight, and for making a reservation on its website. These additional charges average $80 per passenger. Suppose a random sample of 70 passengers is taken to determine the total cost of their flight. The population standard deviation of total flight cost is known to be $40. (a) What is the population mean cost per flight in dollars? $ (b) What is the probability the sample mean will be within $10 of the population mean cost per flight? (Round your answer to four decimal places.) (c) What is the probability the sample mean will be within $5 of the population mean cost per flight? (Round your answer to four decimal places.)