An engineer, a research scientist, and a salesman....

....are returning together from a customer meeting in a remote location. Late at night, their car breaks down on a rural road in an area where a cell phone signal is unavailable.
Looking for a place to spend the night, they knock on the door of an old farm house.

The farmer invites them to spend the night, but tells them that he has only room for two of them; the third will have to sleep in the barn with the cow and the pig.

The engineer volunteers to sleep in the barn. "I'm sure I can design a suitable bed out of what's there," he said, as he left.

About 30 minutes later, there's a knock on the farmhouse door. It's the engineer. "Sorry, he says, "I got along fine with the animals, but my allergies to hay are too severe. I can't sleep out there."

The scientist immediately volunteers to take his place and leaves for the barn.

About 30 minutes later, there's another knock. It's the scientist.
"I thought I could do it, the animals were easy to get along with, but my back flared up, and I can't sleep out there."

"Fine, fine," says the salesman, "I'll show you both how it's done." He leaves.

Fifteen minutes later, there's a knock at the door. It's the cow and the pig......