A plane crosses the Atlantic Ocean (3000 miles) with an airspeed of 500 miles per hour. The cost C (in dollars) per passenger is given by
C(x) = 100 + x/9 +36,000/x
where x is the ground speed (airspeed + wind).
(a) What is the cost when the ground speed is 370 miles per hour, 520 miles per hour?
(b) Find the domain of C.
(c) Use a graphing calculator to graph the function C=C(x).
(d) Create a TABLE with Tbl Start = 0 and ATbl = 50.
(e) To the nearest 50 miles per hour, what ground speed minimizes the cost per passenger?