A、Because they need to use the plane. B、Because they have to repair the engine. C、Because they want to save the cost. D、Because

M: Alexandra, you worked at an airport before. You worked in Aviation.
W:(12)Yes, my previous job was to write contracts for_ an aviation company, we bought and sold airplanes and aircraft engines, so we did a lot of marketing and leasing and speaking to people from different countries, and airlines wanting to buy? equipment, so a lot of negotiations.
M: Can you explain what leasing is?
W:(13)Leasing is when our company owns a piece of equipment, either an airplane or an engine and a customer has a need, for example, if their airplane has to do some maintenance, and they need a replacement, then we will let them use our airplane for a certain amount of months, like you rent a car.
M: Oh, wow. And you lease not only the plane but engines as well?
W: Sometimes you have an airplane that’s delayed at the airport because of some reason and they need to swap an engine out, or whatever.
M: Right before the plane takes off, they sometimes switch engines?
W: They’ll take the passengers off and put them on another plane because it takes a lot longer than the 10 or 15 minute turn around, but, you will have, it’s more an emergency type of situation,(14)so they’ll take the engine off, and it might be and overnight deal so we go ahead and furnish a replacement engine until they can move that plane back to where it belongs or have the engine repaired.
M: So can you lease a pilot?
W:(15)Yes! you can lease a crew. It’s called a wet lease, and we used to do dry leases meaning we only provided the equipment but a wet lease includes a full crew that will fly the airplane, flight attendants, etc.
12. What was the woman’s previous job?
13. What does the woman say about leasing?
14. Why do the airlines put the passengers on another plane?
15. What kind of people are included in a wet lease?