Roy Travel offers helicopter service from suburban towns to John F. Kennedy International Airport in New York City. Each of its 12 helicopters makes between 1,200 and 1,700 round-trips per year. The records indicate that a helicopter that has made 1,200 round-trips in the year incurs an average operating cost of $900 per round-trip, and one that has made 1,700 round-trips in the year incurs an average operating cost of $700 per round-trip.

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 ofround-trips it makes to JFK airport during the year.
2.	Give examples of costs that would be included in a and in b.
3.	If Roy Travel expects each helicopter to make, on average,1,500 round-trips in the coming year, what should its estimated operating budget for the helicopter fleet be?