An airline has to assign flight attendants to flights. There are 10 flights a day. Each flight requires a certain number of flight attendants, which varies with the size of the plane. The company employs 20 flight attendants, all of whom speak English.

There are certain constraints on the composition of each crew. Each crew must contain a certain minimum number of senior and junior staff and certain minimum numbers of attendants fluent in the following languages besides English: French, German, and Spanish. Flight attendants must rest at least two flights between assignments.

You will design the model so that it can be extended; the number of flights and the constraints on the composition of the crew can be easily adjusted.

Here is a table with the 10 flights and their staffing requirements:

Here is a table listing staff and their attributes:

The first step in modeling and solving a problem is to write a natural language description of the problem, identifying the decision variables and the constraints on these variables.

Write a natural language description of this problem. Answer these questions: