A woman brought a very limp duck into a veterinary surgeon.
As she lay her pet on the table, the vet pulled out his stethoscope and listened to the bird's chest.
After a moment or two, the vet shook his head sadly and said," I'm so sorry, your pet has passed away.
"The distressed owner wailed, " Are you sure?"
"Yes, I'm sure. The duck is dead," he replied.
"How can you be so sure", she protested. "I mean, you haven't done any testing on him or anything. He might just be in a coma or someth…