10-27 Estimating a cost function, high-low method. FlyHigh Vacations offers helicopter service from suburban towns to Heathrow Airport in the United Kingdom. Each of its 10 helicopters makes between 1,000 and 2,000 round-trips per year. The records indicate that a helicopter that has made 1.000 round-trips in the year incurs an average operating cost of $350 per round-trip, and one that has made 2.000 round-trips in the year incurs an average operating cost of $300 per round-trip. Required 1. Using the high-low method, estimate the linear relationship y = a + bX, where y is the total annual operating cost of a helicopter and X is the number of round-trips it makes to Heathrow Airport during the year. 2. Give examples of costs that would be included in a and in b. 3. If FlyHigh Vacations expects each helicopter to make, on average, 1,200 round-trips in the coming year, what should its estimated operating budget for the helicopter fleet be