An Airline with Two Types of Airplans, P1 and P2

An airline with two types of airplans, P1 and P2, has contracted with a tour group to provide transportation for a minimum of 400 first class, 900 tourist class, and 1500 economy class passengers . for a certain trip, airplane P1 costs $10,00 to operate and can accommodate 20 first class, 50 tourist class, 110 economy class passengers. Airplane P2 costs $8500 to operate and can accommodate 18 first class, 30 rourist class, and 44 economy class passengers. How many of each type of airplane should be used in order to minimize the operating cost?

A) 14 P1 plans and 7 P2 plans
B) 9 P1 plans and 12 P2 plans
C) 5 P1 plans and 22 P2 plans
D) 9 P1 plans and 13 P2 plans