Formulate a linear programming problem that can be used to solve the following question. An airline has three types of airplanes and has contracted with a tour group to provide transportation for a minimum of 72 first-class, 62 tourist, and 108 economy-class passengers. The first plane costs $3900 for the trip and can accommodate 34 first-class, 10 tourist, and 30 economy-class passengers; the second plane costs $4800 for the trip and can accommodate 14 first-class, 10 tourist, and 42 economy-class passengers; the third plane costs $6100 for the trip and can accommodate 24 first-class, 24 tourist, and 14 economy-class passengers. How many of each type of airplane should be used to minimize the operating cost? x = ---Select--- y = ---Select--- z = ---Select--- ---Select--- F = (objective function) Subject to (first-class passengers) (tourist passengers) (economy-class passengers) x Correct: Your answer is correct. 0, y Correct: Your answer is correct. 0, z Correct: Your answer is correct. 0 (nonnegativity constraint)