Have you heard about the blind man who saw the accident and the dead man who heard it?
Blind and Dead
Explanation
Explain Bear
Hey, listen up, buttercup. This joke is playing on the irony of two contradictory situations. A blind man can't see, but supposedly "saw" an accident, and a dead man can't hear, but supposedly "heard" it. It's funny because it's impossible, like you acing a pop quiz!