A man was in the kitchen making a lot of noise! His wife comes in and asks why he was making so much noise? The man replies: "I am killing flies." A short time later his wife came back and he was still making lots of noise!
She asks: "Well, Mr.Big Shot, how many flies have you killed?" He says: "I have killed seven flies! 4 males and 3 females." She says: "Right, how can you tell the sex of flies?" He says: "Very easy: the 4 flies in my right hand are males. When I killed them, they were all on bear cans!" Then she asks: "If you are so smart, how can you tell the sex of the females?" He says: "The three in my left hand, they were all on the phone!!!"