An old man went into the sperm bank and says to the nurse, “Miss, I want to make a contribution.”
The nurse laughs and says, “Get out of here, old man!”
He says, “Please, nurse I can do it.”
Cocking one eyebrow, she hands him a jar and says, “Go in that room. You have 15 minutes.”
Exactly 15 minutes later, he comes back with an empty jar.
He hands it to the nurse and says, “Nurse, I twisted and I pulled, but I just couldn’t get the lid off the jar.”