I said it should be "a", he said it should "b". When I insisted, he said, "want to bet?"
I said "sure". He took out one dollar, and so did I. I handed the 2 dollars to a third person. Then we asked our user for the right answer. It turned out I was right.
My manager happily let me keep the money. I said "Thank you for acknowleging that I was underpaid for my knowledge, and thank you for making it up."
