Katie and Sam are sitting on the front porch snapping green beans.

Sam:  Look I can snap them with only one hand.

Katie:  It takes less time if you use two hands.

Sam:  I have super snapping abilities though.

Sam:  (about one minute later)  Okay, I am done now.

Katie: Will you please pick up that bean you dropped and hand it to me?

Sam: What?

Katie: Oh never mind you just stepped on it and smashed it.  Just throw that one away.

Sam: Why?

Katie: We don’t need our food to be a test of our immune systems.