A woman brings a very limp duck into a veterinary surgery. As she lays the duck on the examination table the vet pulls out his stethoscope and listens to the duck's chest for signs of life. After a few moments the vet shakes his head and turns to the woman and says sadly, "I'm sorry but the duck has passed away." The distressed owner wails, "Are you sure?" "Yes of course I'm sure. The duck is dead," he replies. "How can you be so sure?" she protests. "I mean you haven't done any testing - he might be in a coma or something." The vet rolls his eyes and leaves the room and returns with a black Labrador. The duck's owner looks in amazement as the dog stands on his hind legs, puts his front paws on the examination table and sniffs the duck from top to bottom. He then looks at the vet and with sad eyes shakes his head. The vet pats the dog on the head, takes him out and returns a few moments later with a cat. The cat jumps on the table and also sniffs the duck from beak to tail and back again. The cat sits shaking its head, meows softly, jumps from the examination table and strolls out of the room. The vet looks at the woman and says, "I am sorry, but as I said, this is most definitely, 100% certifiably, a dead duck." The vet turns to his computer terminal and after hitting a few keys a bill is printed off, which he hands to the woman. The duck's owner, still in shock, takes the bill. "$450!" she cries "$450 just to tell me my duck is dead?" The vet shrugs. "If you had accepted my word for it, the bill would have only been $30, but, with the lab report and the cat scan - it all adds up!!!!!!."